Make a dough with flour, salt, oil, and water. Knead the dough until it no longer sticks to your hands, otherwise work in some more flour. Then let it rest for at least 30 minutes.
Mix the sour cream until smooth and season with a little salt, pepper (you can also add some nutmeg if you like). Peel the onion, halve it and cut it into thin strips.
Now roll out the dough on a floured work surface with a rolling pin until nice and thin and place it on a baking tray or baking stone. Now spread with sour cream, spread onion on top, and sprinkle with the bacon.
Bake in the preheated oven at least 200 °C for a good 20 minutes.