Apple Cake with a Cinnamon Meringue Topping

I love meringue, one of my favorite cakes is the rhubarb meringue that I posted quite a while ago. So I was very excited when I came across this recipe for an apple cake with a cinnamon meringue topping.

Ingredients:
Baking sheet
some extra flour

Yeast dough:
200 ml milk
25 g butter or margarine
375 g wheat flour
1 package active dried yeast
50 g sugar
2 teaspoons vanilla sugar or 1 teaspoon vanilla extract
1 pinch of salt
3 egg yolks

Topping:
3 pounds of apples
1 package vanilla pudding and 2 tablespoons of sugar or Jell-O
400 ml milk

Meringue:
3 egg whites
100 g powdered sugar
1/2 teaspoon cinnamon
Optional: Sliced hazelnuts or chopped walnuts

Preparation:
1. Warm up milk, dissolve butter or margarine in warm milk. When milk is lukewarm, stir in sugar, salt, vanilla and yeast.
2. Sift flour into a bowl. Make a little dent into the middle of the flour, then pour in the milk-yeast mixture. Cover bowl and let yeast become active for about 10 minutes.
3. Add egg yolks and knead everything into one smooth dough. Cover dough and let rise until the dough has visibly increased in size.
4. Peel and core apples, cut into quarters, then cut into slices.
5. Knead dough on a floured surface, roll out on put on a baking sheet. While yeast is rising again, prepare vanilla custard of Jell-O. Spread custard or Jell-O onto yeast dough, then add apple slices.
6. Bake cake at 180 degrees Celsius (350 F) for about 25 min. In the meantime, prepare meringue.
7. Whisk egg whites to stiff peaks, slowly add powdered sugar and cinnamon, and whisk until stiff. Fill meringue into a piping bag and decorate the cake. Sprinkle nuts on top of the cake and bake for another 15 min.

Comments:
1. The bottom was very crunchy when the cake was fresh, but the next day it had softened.

Photo to be added later