Preheat the oven to 180C/160C fan.
Line an 8" square baking tin with parchment paper.
For the crumble mix, place the flour, oats, soda and cinnamon into a bowl and mix.
To this add the butter, oil, maple and apple juice.
Mix to form a crumble mix.
Add 1/2 of this mix to the base and press down with a spoon to compact.
Place in the fridge while you make the filling.
For the filling, add the yoghurt, frozen berries, corn flour and maple syrup to a bowl and mix well.
Spoon this into the chilled base and spread to cover.
Sprinkle the remaining crumble mix on top and bake in the preheated over for 40 minutes or until golden brown all over.
Remove, chill and portion.
