For the tarte flambée, dissolve yeast in a little water, wait 10 minutes. Knead into a dough with flour, oil, remaining water and salt. If it sticks, add more flour.
Let rise in a warm place for 30 minutes. Cut thin slices of onion and narrow strips of bacon. Preheat oven to 220 °C (convection oven).
Roll out the dough as thinly as possible, spread crème fraîche on it first, then bacon and onions evenly.
Bake the tarte flambée for 15-20 minutes until brown and crispy.
Preparation Tip:
For the tarte flambée you can use ham instead of bacon.