For the tarte flambée, preheat the oven to 250 °C (hot air). Roll out the pizza dough (if you have more time, you can of course make it yourself) and spread it thinly with crème fraiche.
Top with onions, mushrooms, ham and arugula and sprinkle with cheese. Season with pepper and add other spices to taste (chili, oregano, herb salt, etc.).
Put the tarte flambée in the oven for about 10 minutes, until the cheese is melted and the arugula is crispy but still nice and green.