For the pizza dough dissolve fresh yeast and 1⁄2 TL sugar in 140 ml lukewarm water and let it rise for about 10 minutes. Mix 450 g flour and semolina in a bowl. Add yeast water and 150 ml lukewarm water, knead everything with the dough hooks of the mixer.
Cover the dough and let it rest for about 5 minutes.
1⁄2 Knead the salt and oil into the dough. Divide the dough into 4 equally sized pieces, form into balls, cover and leave to rise in a warm place for about 30 minutes.
For the topping, stir the crème fraîche until smooth. Season to taste with salt, pepper and sugar. Peel onions and cut into fine slices. Wash, quarter and core the apples. Cut the apple quarters into thin slices.
Preheat oven (electric cooker: 225 °C/circulating air: 200 °C/gas: see manufacturer). Line baking tray with baking paper. Wash the thyme, shake dry and pluck the leaves from the stalks. Grate cheese finely.
Roll out the dough balls one after the other on a floured work surface to make thin pizzas (approx. 25 cm Ø). Place 1 pizza on a baking tray and spread the dough with 1⁄4 crème fraîche. Cover with onion and apple wedges.
Finally, sprinkle each 1⁄4 with thyme and cheese. Bake in a hot oven for 10-12 minutes.
In the meantime, prepare and bake the remaining pizzas one after the other with the other ingredients in the same way. Remove the pizzas from the oven. Sprinkle each with 1 tbsp. acacia honey and sprinkle with coarse pepper.