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
I cannot WAIT to try rhubarb. These bars sound amazing!
It is so neat hearing about all your different travels. You get to see and try and watch so many things I never would’ve thought of! Keep up the fantastic blogging, even though you have so much going on!
Thanks so much, Mary Frances … hope you are having a great time on vacation! We’re getting through our list of things to do, but have got to go back to Australia again soon. Can’t believe it! Please DO try some rhubarb … you’ll love it!
Sounds like your parents have a wonderful garden/greenhouse. Thinking we might see a tomato recipe soon from you as well……. Love oaty crispy sweets, they are my favorite, bet the ginger gave it a nice flavor. That’s really a nice way to face and handle change Helen, always think about what is good that is happening now.
My dad is busy tending the tomatoes every evening after work so I’m sure it’ll be a good crop. I don’t think we’ll be here to enjoy them, though (got to go to Australia again). I wish we were, because tomatoes are very expensive in Australia believe it or not (there I go comparing again!). Hope you are enjoying Oregon, Cheri!
Hi Helen!
I totally agree with you when you say that when we are in another country, we keep comparing with another one. I happens to me when I moved to Canada from France, I let you imagine the supermarket comparison I was making…
Funny enough, now, I adopted Canada as my home (or Canada adopted me :)) and I compare it with France when I visit… Could I re-adapt one day? not sure!
Can you picture living again in England after so many “homes”?
Anyway, I am going into a conversation alone! Again, you do need to move to Canada so we can have coffee chat as I mentioned before! This recipe would work perfectly at any time for me!
Cheers,
Melanie
PS: Thanks for the head-up for my comment problem on my blog! I really appreciate it!
Hi, Melanie! You know what? If I ever visit Canada (which I would love to some day – I visited Quebec many years ago but there is still so much of Canada to see) we will have that coffee chat. Or if you ever visit the UK! I’m wondering if I can adapt back to the UK now too after so many years, especially right now as I watch the rain streaming down the windows for the third entire day in a row. (oops – better not complain!) Glad you like the recipe!
Love the sound of these oat bars! I can only sometimes find rhubarb but I’ve seen it at the store the last week or two!
It is hard not to compare too much – when we first moved here from DC I found myself doing the same thing. But we love it in NC now : ) It was just such a change from DC!
It’s funny to think that you live in such a big country that states can be so different from each other. I would love to go on one of your big US road trips to experience some of those differences! It is hard not to compare, isn’t it? I’m sitting here right now trying not to compare the 3 rainy days we’ve just had here with the sunny weather I’m sure they’re enjoying right now in Greece. (I won’t, I won’t.)
So glad you like the bars and … snap up that rhubarb while you can! Or hunt out a friendly neighbour with a patch in their garden!
That oaty mixture is singing sweet nothings to me because it looks marvelous! What a great treat!
Thanks, Pamela! 🙂
This looks fantastic! I have never ever had rhubarb, I keep seeing it on blogs but I don’t know of anyone that cooks with it. That is one reason why I love blogging and the blogging community, there are so many great ideas out there and this makes it so easy to share them!
I totally agree, Annie. I see ingredients that I’ve never cooked with all the time on blogs – healthy ingredients, especially. If you can get hold of some rhubarb, I’d definitely try it just to see what you think. I don’t think you’ll be disappointed. So glad you like the recipe!
They look tasty – especially with ice cream on top!
Thanks, Pam! 🙂
Oh, YUM! These are like a rhubarb crisp in bar form! LOVE it!
That’s exactly what they tasted like, Liz, but with a chewier layer on the bottom. Exactly as I wanted them to be! Glad you like them!
Reading your blog makes me want to travel so much more! Now if I could just win the lottery and vacation for a few years : )
These rhubarb and ginger oaty slices sound delicious. So happy rhubarb is in season!
We always want what we don’t have, I guess. I would give anything right now to just get settled … but trying to see the ‘excitement factor’ of the travelling here and there!
So glad you like the rhubarb slices … I have to admit I was pretty pleased with how they turned out. 🙂
It is so interesting how people from different places do things so differently. It can definitely be hard to leave things behind that you loved, but I always like that think that better things are on the horizon. Love these rhubarb oaty slices!! And I love the word “oaty”! That is awesome that they have a garden with fresh tomatoes AND rhubarb! Rhubarb is so pretty when it grows. I really need to start using rhubarb more while it is still in season, because I really love its tartness 🙂
Yes, it has such a unique flavour, which I love. So glad you like the slices (and the word ‘oaty’ – OK, I admit it, I did make that one up) and your point about looking to better things on the horizon is lovely … totally agree.
I know what you mean about comparing different cultures, etc. It’s so fascinating to see how others live/be happy in conditions and situations that I would be incredibly uncomfortable with.
And this recipe just looks incredible! I wish I had the problem of too much rhubarb! And it totally does make your tastebuds sing like nothing else. The ground almonds would be perfection with this! Mmm mmm!
So glad you like the recipe, Allison. I agree that having too much rhubarb is such a ‘terrible’ problem to have! 🙂
Helen, I live in Canada but I am originally from Brazil so I know well what you mean by comparing things like the weather and the food when you live in a different country. But, it is hard at first but if you focus on what’s good and exciting about the new place you live really well 😉
So, I love your recipe. I don’t think I’ve ever cooked with rhubarb before, but I must try it soon!
I really hope you do have a go at a rhubarb recipe some time, Olivia. It isn’t something I eat very often (I don’t think I’d had any for years before last week), but it’s absolutely delicious. 🙂
I’m so excited to see this recipe because rhubarb is coming into season here very soon! I love picking rhubarb and dipping it into sugar – like you said, maybe even a part of childhood. With the oatmeal, this is kind of like a breakfast option. Looks delicious and kind of nutritious too, just the thing to bring to a family picnic for me =) Father’d Day picnic I think since your dad liked it so much.
That’s a lovely idea to make these slices for Father’s day! They are fairly hearty and substantial as a dessert which sort of matches dads, doesn’t it? Haha! Fabulous idea to eat these for breakfast, too. I think that would be perfectly acceptable because of the oats and fruit and relatively low fat and sugar amounts. So glad you like them and hope you can enjoy your rhubarb season soon!
A rhubarb patch! Divine. I’m so jealous. You’re living the rural English idyll. No such fun to be had in South London. Xxx
That is definitely one of the many advantages of lodging with the parents for a while. Too bad it isn’t my rhubarb patch or my tomatoes … some day, though, I will have the same! 🙂
I am becoming more and more fond of rhubarb and we have a massive patch of it and have recently made tons of chutney. OH is the flap jack maker and I will pass on your recipe to him.
Oooh, rhubarb chutney! Now there’s an idea for what to do with my dad’s remaining rhubarb! 😉
Wow, beautiful. I might be the only blogger left that is yet to try rhubarb.
Really, Kathy? Oh, you definitely must try it soon! 🙂
I don’t think I’ve ever cooked with rhubarb before, but I think now I have an excuse to go find it at the grocery store 😉
Yeah, go and find some! It’s beautiful!
Wow you’re parents have a greenhouse? I need that! Today there was a huge storm and it seems to have ruined some of my plants 🙁 This slice looks utterly gorgeous! xx
Yes, the greenhouse is full of lovely tomatoes. Wish it was mine! Sorry about your plants … that’s so sad!
Those look delicious! I love the addition of ginger, that’s one of my favorite flavors and it sounds like it would go splendidly with rhubarb. 🙂
Thank you so much for reading and so glad you like these. The ginger flavour came through just enough in these slices and went so well with the rhubarb. So glad you like them! 🙂
J’ai bien aimé ta petite histoire. Ton dessert il pareil trop bon! J’espère que à partir de maintenant ton père il ne se plaindra plus d’avoir de la rhubarbe dans son jardin! 😉
Coucou, Eva, et merci! Non, tu as raison, mon pere ne se plaindra pas du tout! je suis ravie que tu aimes ce dessert. 🙂