For the dough, knead the flour with soft butter, salt and water to form a smooth, soft dough and line the mold up to the top with it.
For the filling, whisk the egg with the sour cream and stir in the grated cheese. then fold in the onion and bacon cubes and season with salt, pepper and nutmeg.
Put the mixture on the dough and then bake on the middle rack at 180 ° C for about 35-45 minutes.