I found it on simplyrecipes.com, but have slightly changed it though — to make it lighter and healthier.
Start to pre-heat the oven (200 degrees)
In a medium bowl mix flour, baking powder, butter, egg and milk.
In a smaller bowl mix 4 tablespoons of brown sugar with cinnamon.
Pour half of the first mixture (flour one) on a baking dish and lay the apples slices (in order to cover all the dish).
Sprinkle the apples with the second mixture (cinnamon-sugar), reserving a little bit to add on top of the cake.
Spread the rest of the flour mixture over the apples. Sprinkle the remaining sugar mixture on top with some dark chocolates chips.
Bake for 20-25minues
What you need:
16 tablespoons of flour
1 teaspoon of baking powder
5 tablespoons of brown sugar
1 teaspoon ground cinnamon
2 tablespoons of butter (salted)
2 beaten eggs
8 tablespoons of whole milk
1 baking apple
Dark chocolate chips