For the yeast dough, mix the milk with the yeast and sugar until the yeast has dissolved.
Put the flour, salt and egg yolk in a bowl, then add the yeast mixture and knead until a lump has formed. Add the very soft butter and continue kneading for about 10 minutes until the butter is completely kneaded and a smooth dough has formed.
Cover with a trash bag and let rise for 40 minutes.
In the meantime, grease and flour a springform pan. Peel the apples eighth and cut into not too small cubes, drizzle with a little lemon juice and chill.
Take the dough out of the bowl, press it flat with your hands briefly to degas it. Roughly roll out the dough and place in the mold, then distribute it in the mold so that the entire springform pan is covered. Cover and let rise for another 30-40 minutes.
Preheat the oven to 180 ° C top / bottom heat.
For the topping, mix the very soft butter with the sugars and cinnamon with the stirrers.
After the dough has risen, press as many indentations as possible into the dough with your thumb and distribute the butter in the indentations with the help of a teaspoon.
Press the apple pieces into the hollows and pour the remaining apples over them. Sprinkle with brown sugar and cinnamon to taste.
Bake for about 30 minutes on the middle rack, possibly switch to top heat or grill 5 minutes before the end of baking. Cover with the powdered sugar immediately after baking.
Enjoy immediately or later with or without whipped cream.