Preheat oven (electric cooker: 200 °C/ circulating air: 175 °C/ gas: level 3). Heat the fat pan of the oven (32 x 39 cm) in it. Mix eggs, milk, mineral water and flour to a smooth dough.
Season with salt and pepper. Place baking paper on the hot fat pan and brush with oil. Pour the egg mixture onto the hot baking tray and pre-bake for approx. 20 minutes until the egg mixture has set and slightly browned.
Peel onions and cut them into rings. Heat 1 tablespoon of lard in a pan. Brown the onion rings in it, take them out. Clean and clean the mushrooms and cut them into thick slices. Add 1 tablespoon of lard to the pan.
Sauté the mushrooms well in it, season with salt, pepper and Italian herbs. Wash, clean and slice the tomatoes. Drain the tuna and pluck into large pieces. Take the fat pan out of the oven and let it cool down a little.
Mix the gipsy sauce with tomato paste and spread it on the pancake. Cover one half with tomatoes, onions and tuna and sprinkle with thyme. Quarter the ham slices. Cover the other half with mushrooms and ham.
Sprinkle cheese on pizza. Bake for another 10 minutes. Garnish half of ham with basil, tuna with thyme.