Pre- heat oven to 180C and line a 20cm square tin
Put flour, oats, cinnamon, coconut, baking powder and sugar in a bowl and mix well. Add the butter and vanilla essence and mix again.
Spread 2/3 of this mixture over the base of the tin pressing down with your fingers.
Spread and top your slice evenly with apple pureed apple.
Top your slice evenly with remaining crumble mixture and gently press down.
Bake for about 25 minutes or until slightly golden brown.
Allow to completely cool in the tin before slicing into your preferred size pieces.
The slice will continue to set in the fridge and therefore become more portable for school lunchboxes.
Store in an airtight container in the fridge.