Pre-heat the oven to 355F / 180C and grease a medium sized high-sided baking dish with butter.
Mix together the flour, sugar and lemon zest in a medium bowl.
Pour the milk / butter mixture into the dry ingredients and stir until well combined.
Empty the batter into the baking dish.
Mix the sauce ingredients together, then carefully pour over the batter in the baking dish. Bake for about 35 minutes or until the top is golden brown and the sauce starting to bubble around the sides.
Take out of the oven, then leave for 10 to 15 minutes to allow the sauce to thicken slightly before serving.
Sprinkle with icing sugar and serve immediately with vanilla ice cream (if you like).
A note on the appearance!
Know before you make it that this dessert is DELICIOUS but it's probably never going to win any beauty contests! It might be one to reserve for you and your family rather than serving it to guests you're wanting to impress ;-)A note on the consistencySome readers have reported this dessert to be 'too runny'. There IS a lot of sauce, and when you first take it out of the oven it's bubbling and runny looking.Leave it for about 15 minutes however and it should thicken up nicely, leaving the equally as delicious cake on the top.
A note on the flour
The self raising flour in this recipe is crucial for it to work, so make sure you don't use plain flour instead.If you don't have any self raising flour, simply add 1.5 teaspoons of baking powder and half a teaspoon bicarb of soda/baking soda for every cup of flour.It's also worth noting that self rising flour in the USA is NOT the same as self raising flour in the UK or Australia. If you're in the USA, I'd recommend using the above formula to make your own self raising flour. Good luck!