Flammkuchen with Ham and Red Onion

In a large bowl, mix the flour with the salt. Gently heat the mineral water together with the lard (or oil) until the mixture is lukewarm. Pour the liquid over the flour and knead the dough for about 5 minutes, until it becomes elastic and no longer sticks to your hands. Wrap it in cling film and leave it in the refrigerator for at least 30 minutes.

Preheat the oven to maximum temperature (250 °C). Leave the baking tray inside to heat up well. Cut the red onion into very thin, almost transparent slices, so they cook quickly. Prepare the ham or bacon cut into cubes.

Divide the dough into two equal parts. Roll out each piece on a lightly floured surface until you get a very thin sheet. Transfer the sheet onto a piece of baking paper. Spread each sheet with sour cream, leaving the edges free. Season with black pepper and add the ham, red onion, and grated cheese.