Blueberry Rhubarb Crumble Bars

Make The Blueberry Rhubarb Filling:

Add your rhubarb, blueberries, sugar, cornstarch, lemon juice, and cinnamon to a pan and set on a medium-low heat with the lid on. Stew for approximately 15 minutes, until the rhubarb is soft and the fruit has stewed together and is jammy.
180 g frozen rhubarb, 150 g blueberries, 100 g golden caster sugar, 2 tbsp cornstarch, 1 tsp cinnamon, 1 lemon

Make The Crumble Bars:

While the jam is cooking, preheat the oven to 180°C and line a baking dish with parchment paper. Make the crumble.
Add your flour, oats, sugar, baking powder, and salt to a mixing bowl and mix.
120 grams rolled oats, 200 grams flour, 200 grams brown sugar, ½ teaspoon baking powder, ¼ teaspoon salt
Add the cubed, softend butter and combine with cleamfingers to creature a crumble texture.
170 grams cubed
Set aside about ⅓ of the crumble in a different bowl.
Press the remaining two-thirds of the mixture into your baking dish, ensuring it's evenly pressed down in all corners. Bake for 10 minutes.
Once you've removed the base from the oven, pour over your rhubarb and blueberry filling, then grate over the lemon zest. Then, sprinkle over the remaining crumble mix.
Bake for a further 25 - 30 minutes
Remove the bars from the oven and allow to cool - I chill my bars for several hours in the fridge before cutting to allow them to really firm up before cutting into bars