Sift flour, mix with salt and baking powder. Add curd, milk and oil and knead heartily until a smooth dough is formed. Leave to cool for 20 min. Preheat electric kitchen stove to 200 °C.
Cut bacon into tender strips. Peel onions, slice into rings with vegetable slicer. Fry bacon briefly in a frying pan without fat, remove. Melt butter, sauté onions for 7 minutes until soft. Peel apples, clean and cut into narrow slices. Mix with onions, sour whipped cream, crème fraîche, walnuts, eggs, cheese, salt and pepper. Place the dough in a greased tart springform pan, raising the edge about 2 cm. Pour in filling, spread bacon evenly on top. Bake for 40 minutes on the lowest rack (gas: level 2).
by Matthias Kerl
Our tip: Use a bacon with a strong flavor – this will give this dish a special touch!