Flammkuchen (German tarte flambée)

1. Preheat the oven to the highest setting (about 250 °C), ideally with the baking tray inside.

2. Knead the flour with the water, oil and salt into a smooth, elastic dough and let it rest for 15 minutes.

3. Stir the crème fraîche with the sour cream, salt, pepper and a pinch of nutmeg until smooth.

4. Slice the onions into very thin rings and cut the bacon into thin strips.

5. Roll the dough out very thinly on baking paper, spread with the cream and scatter with the onions and bacon.

6. Slide it onto the hot tray and bake for 10-12 minutes until crisp; serve hot, cut into pieces.

Tip: The secret is very thin dough and maximum heat - that's how the edges get blistered and crisp.