Crumble the yeast and mix with sugar until the yeast becomes liquid. (This saves the pre-dough.) Put flour, 1/4 teaspoon salt, oil and 175 ml lukewarm water into a bowl. Add mixed yeast and knead immediately to a smooth dough. Cover the dough and let it rise in a warm place for about 30 minutes
Season sour cream with a little salt and pepper. Drain the sauerkraut in a sieve and mix with marjoram. Wash apple, halve, core and cut into slices. Cut sausage into slices
Line baking tray with baking paper. Halve the dough. Put 1 half on a baking tray and roll out very thin oval. Spread half the sour cream on the bottom. Cover with half the sauerkraut, half the apple slices and half the black pudding. Bake in the preheated oven on the lower shelf (electric oven: 250 °C/ convection oven: 225 °C/ gas: level 5) for 10-12 minutes. In the meantime, process the remaining dough and topping in the same way
Take out the tarte flambée. Bake the 2nd tarte flambée in the same way. Garnish the tarte flambée with marjoram. Add mustard if necessary.
Waiting time approx. 30 minutes