Use the ingredients for the dough to make a dough and refrigerate for 1 hour.
Pour into a pie pan (or 26 mm pan) lined with baking paper and refrigerate for another 15 minutes.
Mix all ingredients for the filling. Place on the prepared base and bake at 200 ° C for 30 minutes. Then reduce the temperature to 190 ° C and bake for another 10 minutes.
In the meantime, prepare the topping. Mix the flour, 4 tablespoons of sugar, baking soda, baking powder, salt and butter with your fingers. Mix the buttermilk, egg and vanilla extract. Then mix both ingredients with the mixer.
Now place the topping on the baked cake, then sprinkle 1 tablespoon of sugar over it. Bake the cake for another 20-25 minutes, then let cool for 20 minutes.