Easy Rhubarb Bars
on Apr 24, 2025
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With a zingy layer of rhubarb sandwiched between two soft and chewy layers of oats, these rhubarb bars are like a cross between a fruit crisp or crumble, and a granola bar! With just 7 ingredients, they’re a unique and yet easy spring treat to make use of this sharp and lively seasonal fruit.
Have you ever had a rhubarb patch in your garden? If so, you’ll know that the long, thick stalks that look like bright red and green celery but taste like a delicious fruit can go crazy in the spring.
Luckily, although it’s very sour when eaten raw, cook it with a little sweetness and it’s perfect in cakes, crisps, crumbles… and these delicious tangy and chewy rhubarb bars!
If you don’t have any rhubarb in your garden, see if your local supermarket or farmer’s market has some. Made with oats, almond flour, brown sugar, honey, and a hint of ginger, this healthy(ish) rhubarb recipe is as delicious as a rhubarb crisp or crumble – but on the healthier side!
Why you’ll love them
Here’s a summary of what I think you’ll love about these easy rhubarb bars:
- Made with just 7 simple ingredients. Apart from the rhubarb, you’ll only need oats, almond flour, brown sugar, honey, butter, and a little ground ginger.
- Quick and easy. They take less than 15 minutes to make (and then a swift 30 minutes to bake!). You’ll use the same oat mixture for the bottom and top layers, making this recipe a little easier than others like it.
- On the healthier side. Since they’re made with mostly natural ingredients, you can enjoy this easy spring dessert guilt-free.
- They’re so delicious! Slightly crunchy on top, chewy on the bottom and fruity and tart in the middle – for the perfect balance between tart and sweet.
- Snack or dessert? Serve by themselves as a snack, or as a unique dessert with ice cream or cream on top.
Looking for more fruity desserts on the healthier side? Try these healthy blueberry muffins once and they’ll become your go-to muffin recipe!
About the ingredients
You’ll find a full list of ingredients with amounts in the recipe card below. But here’s a summary of what you need to know.
Rhubarb: The star ingredient! You only need about 4 ‘stalks’ of rhubarb. Find out when it’s in season where you live and grab some while you can! Look for medium-thick stalks that are firm, smooth and glossy and a vibrant red, green (or both red and green) color. Cut off the leaves and any tough parts, then chop into small pieces.
Brown sugar: Just a little, to take the edge off the sourness of the rhubarb.
Butter: Both salted and unsalted butter are fine, although a bit of salt always adds balance in a sweet treat.
Brown sugar and honey: You’ll melt these together, so any kind of honey will work. In theory you could skip the sugar and just use honey, but I think the bit of sugar helps the mixture to hold together after cooking. It also adds some flavor and caramelization in the oven.
Feel free to also substitute the honey with maple syrup. One reader even successfully added stem ginger (preserved ginger) and used some of the syrup from the jar instead of brown sugar!
Rolled oats: Make sure that you use rolled oats. Don’t use quick-cooking or instant oats – you really need the coarse chewy-ness of the old-fashioned style ones.
Almond flour: This acts like a regular flour, helping the oat mixture to stay together. This is perfect if you’re looking for a gluten free dessert (just check that the oats you’re using are also gluten free). If you’d rather not use nuts, you can just use all-purpose flour or whole wheat flour.
Ground ginger: For a hint of spicy warmth. I suggest a heaped teaspoon, but you can add even more if you like. For more gingery zing, add a bit of chopped candied ginger, preserved ginger or stem ginger too. Go easy though at first. One or two balls of the ginger is about right for me. You can always add more next time!
Cinnamon and even a pinch of all-spice can be a delicious addition, too.
How to make rhubarb bars
You’ll be amazed how easy these rhubarb bars are to make.
First, prepare the rhubarb! Cook it in a saucepan with a bit of brown sugar. 10 minutes should do it.
This is what you’ll end up with. See how the rhubarb cooks down so quickly!
To make the oat mixture, you’ll start by melting the butter, a little more brown sugar and plenty of honey together.
Stir in the rest of the ingredients – oats, ground almonds and ground ginger.
Now you can begin to assemble the bars. Start by pressing two thirds of the oat mixture into the bottom of a baking pan.
Press it down with a silicon spatula or wooden spoon.
Then spread the cooked-down rhubarb all over the top.
Finally, sprinkle the rest of the oat mixture on top, and bake. It’s ready when the top has started to go a deep golden brown in parts.
Leave to cool before cutting into slices. Alternatively, you can serve the bars as dessert while still slightly warm!
Helen’s Top Tips
- When you spread the final third of the oat mixture over the top, there may be bits of rhubarb still poking through. That’s perfect – just makes the bars look a vibrant pink color when they come out of the oven!
- If you find your bars are browning too quickly on top, you can loosely tent the pan with foil for the last 5–10 minutes to prevent over-browning.
- Rhubarb freezes well so it would be easy to cook down plenty when it’s available to use in this rhubarb bar recipe throughout the year. You’ll need around a cup and a quarter of the defrosted rhubarb mixture to make one pan of bars.
- Not rhubarb season? What a shame! Why not try making the bars with berries, or stone fruit such as nectarines, peaches or plums instead (just don’t cook them first – no need).
- You can also try adding a few strawberries to the rhubarb mixture since rhubarb and strawberries are a perfect match! How about a teaspoon of vanilla, too?
How to eat them
As you take a bite of one of these rhubarb bars, there’s the crumbly, oaty top, then the tangy rhubarb gets your taste buds singing as only rhubarb does. Finally, there’s another slightly chewy oat layer on the bottom.
Here’s how I like to enjoy them:
- as dessert with ice cream (or healthy nice cream!) on top
- as you would a fruit crisp or crumble, with cream, Greek yogurt or custard on top
- completely cooled in a lunch box, at a picnic or BBQ, after school or as a satisfying snack
Recipe FAQs
Nothing! These oat slices are on the more crumbly side when they’re warm, almost like a crumble or crisp. Feel free to eat when still warm, but they’re better eaten with a bowl and spoon. If you let them cool completely, or even chill them in the fridge, they’ll hold together better. I like them both ways!
They are if the oats you use are labelled gluten free. Check the package. If they are in fact gluten free, these rhubarb bars are a great gluten free dessert option!
The rhubarb bars will keep well in an airtight container in the fridge for up to a few days, although they won’t be as crisp on top after the first day. If you’d like to keep them for longer, you can freeze them in freezer bags or an airtight container for up to 3 months. I would suggest reheating them until crisp on top again. You can reheat them straight from frozen for 15 to 20 minutes at 350F/180C or until hot and lightly crisp on top again.
Love the idea of fruit and oats together? Try these easy apple and oat muffins. If you have a little more time, try making this easy apple crumble pie with oats some time as well!
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Easy Rhubarb Bars
Ingredients
For the rhubarb
- 4 rhubarb stalks, with leaves and any tough parts cut off, then chopped into 1-cm pieces
- 2 tablespoons brown sugar
For the oaty mixture
- 3 tablespoons butter, (3 tbsp butter is about 1.5 ounces)
- ¼ cup brown sugar
- 3½ tablespoons honey, any kind since you'll be melting it with the butter and sugar
- 2½ cups rolled oats, NOT quick-cooking or instant oats
- 1 cup almond flour, (sometimes called almond meal)
- 1 teaspoon ground ginger, (add more if you like, and/or a little chopped candied/crystallized ginger for a more intense ginger flavor)
To serve (optional)
- ice cream, cream, yogurt or custard
Instructions
- Pre-heat the oven to 190C/375F (this is for a fan oven – increase to 200C/390F if using a conventional oven). Also line an 8 X 8 inch (20 X 20 cm) cake pan with baking paper.
- Put the chopped rhubarb, brown sugar and 1 tablespoon of water into a large saucepan. Heat on a medium heat, stirring occasionally, for about 10 minutes until cooked down but with some pieces of rhubarb still whole. Set aside.4 rhubarb stalks, 2 tablespoons brown sugar
- For the oat mixture, melt the butter, sugar and honey together in another large saucepan, stirring with a wooden spoon. Take off the heat and stir in the oats, ground almonds and ginger until all the oats are well coated.3 tablespoons butter, ¼ cup brown sugar, 3½ tablespoons honey, 2½ cups rolled oats, 1 cup almond flour, 1 teaspoon ground ginger
- Spoon two thirds of the oat mixture into the lined baking pan and press down well with a spatula or spoon. Spread the cooked rhubarb over the oats, then sprinkle the rest of the oat mixture over the top.
- Bake for 20 to 25 minutes or until the oats are golden brown on top. If you find they are browning too quickly on top, loosely tent the pan with foil for the last 5–10 minutes. Leave to cool before cutting into slices. Alternatively, serve while still slightly warm with ice cream, cream, custard or yogurt on top. Keep in an air-tight container in the fridge for up to a few days.ice cream, cream, yogurt or custard
By “ground almonds” do you mean coarse ground or almond flour?
Hi Melissa! In the UK (where I was when I posted this recipe!) almond flour and ground almonds are interchangeable – so either is fine! Hope you enjoy the recipe!
Hi Helen,
Love your blog, which I have just discovered, and this recipe was exactly what I was looking for, It’s cooling right now.
RAIN IS LOVELY! There would be no lovely rhubarb without it! The smell of the earth, the cool air and it makes everything so green!
It took me ages to readjust after living in Morocco. Last year I went to Greece for the first time and now I will always long for that azure sea!
Love and Thanks,
Rosemary
Hello Rosemary. What a lovely message to wake up to today! I always appreciate feedback, so thank you so much for taking the time to comment.
This is an older recipe with not-so-perfect photos, but I’m so glad it turned out well. This is still one of my dad’s favourite recipes!
I’m so happy you’re enjoying the blog.
Wow, Morocco! I once visited Tetouan for just 1 day from Spain which was an incredible (if not a little nerve-wracking) experience. The food there must be amazing!
Hi this recipe sounds divine and I am about to go pick some rhubarb from my garden and make it right now!
I just wanted to point out however that this isnt a gluten free recipe as oats are what need to be avoided in a gluten free diet, especially with the coeliac disease.
Thanks 😊
Hi Ciara! So pleased you’re going to give this a go (it’s one of my dad’s favourites!). And thanks too for drawing the gluten free issue to my attention. It seems that oats should be gluten free but there can be a problem with contamination, which as you point out can be really disastrous for those with coeliac disease. I think I’ll add a note to my recipe! Thanks again! 🙂
I just made this, so yum! I cooked the rhubarb with some stem ginger and the syrup from the jar instead of sugar, which worked really well. I also replaced the butter with coconut oil which made a nice change. Thanks for the recipe!
Hello, Jess. So happy to hear that you tried this and enjoyed it, and even made some successful substitutions! I must make this again soon – it’s my dad’s favourite!
These look fab! I’ve been given a jar of preserved ginger and wondered if I could use that instead of ground ginger. If so, I wonder how much?
Hello, Maz! Ooh, now there’s a question! You can definitely use the preserved ginger instead of ground. Why not? It’s just for a hint of a gingery taste, after all, so if I were you I’d chop up finely and add one or two balls of the preserved ginger and see how you go with that. Let me know how you go!
Hi, I found the cooking temperature you suggested was too hot. My crumble-topping started to burn. (Using regular bake, not fan-forced). Have dialled it back to 180C and shifted it down a rack level. Is smelling wonderful right now so might have saved it!
Thanks for this GF recipe. What a treat. 👍
Hello Gilly – thanks so much for this feedback on the cooking temperature. Have reminded myself to give this one a go again in my new oven and see if I need to amend. I hope you enjoyed them! 🙂
Argh, I STILL live in a flat with no garden! It drives me mad as I’ve attempted growing bits and pieces in pots but nothing has thrived as yet. These bars look beautiful. Even better with fresh-picked rhubarb in the mix! I’d be interested to know if you think there are any peculiar behaviours amongst Australians? You are right though, stereotypes aside, different countries do seem to have quite distinct behavioural differences xx
It’s actually a tease living here with my parents and their garden for a month, Laura, because I know that I’ll soon be back to a flat with no garden! My one and only attempt at growing something myself was a pot of mini tomatoes on my balcony in Greece, but they turned out really small and tough. So glad you like the bars. Hmmm … Australians … I’ll think about that more when I’m there again this time, but one thing I did wonder is why they think it’s weird to wear slippers when it’s cold! 🙂
I love that you have been to same many countries Helen. I’m moved to different states within the US and too have found many differences. Most notably, when I lived in Eastern Florida everyone would ask my religion. They were obsessed with religion, particularly Baptist. That was hard to deal with because if you said anything other than Baptist they would want to talk your ear off about converting.
Anyhow, I love that you picked your own rhubarb for this treat. It looks delicious!
lol … that’s funny about the Florida baptists, Cindy! That must have got old pretty fast! I find it really fascinating that you have so many differences between states over there in the US. I’d love to do a big road trip one day to experience some of them for myself. So glad you like the rhubarb slices!
Helen, we have to join the rhubarb fan club too and your bars look amazing! Adore the combination of rhubarb and ginger. We feel the same way as you do about new and old places, and it is so interesting and rewarding to experience different cultures, languages and the best of all different cuisines! Hope you are having a wonderful week in beautiful England 🙂
Cheers,
J+C
Oh, please do join the rhubarb club, girls! I can imagine that there is a perfect wine to go with it! I really hope you are both having a beautiful week, too. 🙂
I’m visiting your site for the first time and you baked with one of my favorite ingredients! I love rhubarb, and have been baking a lot with it lately. I’ve only combined it with berries this far, and that needs to change — these look incredible! You’re so lucky you’ve gotten to love in so many different countries — I’ve been to Greece and England and would love to have stayed much longer!
I must have done that just for you, Marcie! I loved your post on the beautiful Mary Frances’ site (isn’t she sweet?) and am looking forward to hopping over to check out your site, too. Thanks so much for dropping by to say hi and so glad you like the rhubarb slices – I was really pleased with how they turned out.
Ah, comparisons are inevitable when moving around, especially for the weather, and especially from warmer to more frizzling 🙂 My husband comes from Provence and I hear it every day 🙂
Haha … yes, I have to be careful that I don’t moan too much about the weather now that I’m here in England. It’s very tempting but I’m trying to follow my own advice and be positive!
I’m so jealous that you get to pick rhubarb, Helen! Rhubarb is one of my favorite pies, yet I only seem to eat it every so often. And these slices look delicious! Now I have another recipe that I can use rhubarb for. Pinned!
Well, I think being able to pick anything at all from a garden or window box or whatever is amazing. I must try to make something else with that rhubarb before I leave my parents’ house. So glad you like this recipe, Gayle, and thanks so much for the pin!
OMG !!!! I am drooooooling !!!! These slices look incrediblyyyy tasty!!!!!! I have never eaten rhubarb before! We don’t get it here! 🙁 But like you said, I’m going to make these with berries! So So perfect!
I think they’ll be fine made with berries, Samina. Actually, easier, because you won’t have to pre-cook the fruit. Let me know how you go if you do make them! 🙂
Yay for looking on the bright side…and for rhubarb! I’m a bit of a rhubarb addict lately. These bars look awesome!
So glad these bars have the approval of a rhubarb addict! 🙂
I definitely need to get me some rhubarb. My neighbor was just telling me that the local farmers market has it now. I need to get myself over there quickly. I’ve been seeing great recipes for rhubarb.
These look fantastic!
Hope you have a beautiful Wednesday!
Yes, get yourself over to that market quick, before it goes out of season! Glad you like these, Melanie. 🙂
Helen I´m always happy to see a recipe with rhubarb in it! I have also a suburban garden here in Germany and every year I harvest about 6kg rhubarb. This year I´ve made already cakes, jam, muffins and chutney, but I still have rhubarb!! Had to freeze then. Thanks for sharing this recipe, it looks delicious 🙂
I love the sound of rhubarb chutney, Karla. Maybe that’s what I should make with my dad’s remaining rhubarb! 🙂
Wow, I would love to be out there picking rhubarb too. I hope to get to try rhubarb sometime. These bars just might be my first try at rhubarb. I like the combination of ginger and rhubarb, it sounds so good.
Yes, the ginger really does go very well with the rhubarb, Norma. I really hope you do get to try rhubarb soon and of course I would feel very honoured if you chose this rhubarb recipe first. 😉
This is such a great idea! yummy and gluten free.
Thanks, Layla. So happy you like them!
What bliss Helen! Freshly cut rhubarb no less. And you know I was similar when I left Australia to live in Japan. It was only after being away that I appreciated how great Australia is to live in.
Right at this moment though I’m not so sure … it has rained here for 3 days straight and no end in sight. Aaargh! So happy that you like the rhubarb slices! 🙂
A rhubarb patch…what a fantastic surprise! The first time I ate rhubarb I didn’t know what to expect, but ended up being completely blown away. Delicious! My boyfriend is crazy for rhubarb so I bet he would love this recipe. I bet I would, too!
Yes, it has such a unique flavour, doesn’t it? I pretty much pounced on that rhubarb patch after I saw it!
So glad you like these, Alyssa!
This recipe sounds so delicious and easy too (which is always a bonus when it comes to baking)! I especially love the combination of ginger and rhubarb.
Also, just a tiny bit jealous of all the wonderful places you’ve lived!
A lot of people say that, Louisa. I don’t think I’ll ever get tired of travelling, but I am ready to settle somewhere now! I was pleasantly surprised by how well the ginger went with the rhubarb. So glad you like these slices!