Bake Play Smile
Place the plain flour, rolled oats, salt, bi-carbonate of soda, raw sugar and brown sugar into a large bowl and mix together to combine. Add melted butter and vanilla extract. Stir until all of the dry ingredients are coated and the mixture is crumbly. Bake for 15 minutes until lightly golden.
Sprinkle the fresh or frozen blueberries over the cooked base.
Place the sweetened condensed milk, lemon zest, lemon juice, egg yolks and lemon extract (if using) into a large bowl. Whisk together until smooth and the filling has thickened slightly. Pour the lemon filling over the blueberries and smooth out with the back of a spoon.
Use your fingers to sprinkle the remaining crumble over the filling. Bake for 23-26 minutes or until golden and crunchy on top.