Mix the margarine and sugar together until light and fluffy.
Beat in the eggs and the apple juice.
Add the flour and cinnamon. Mix until well combined.
Stir in the chopped apple.
Pour mixture into the tin and bake for 5-7 minutes. It will not be cooked this step is just to create a slight sticky sheet at the top so the apple crumble mix will not sink.
While you are waiting make the crumble mix by mixing the butter, sugar, cinnamon and flour together using your fingers till it looks like bread crumbs.
Take the cake out of the oven and place the sliced apples over the top of it then sprinkle the crumble mix over the top.
Sprinkle some brown sugar over this if desired.
Notes
When baked cut the cake into slices. Enjoy! Yum
Recipe by at https://laurasglutenfreekitchen.com/2013/11/gluten-free-apple-crumble-cake-bars/