Cut the onion into fine cubes. Knead the minced beef, onion cubes, 2 egg yolks, breadcrumbs, oregano, salt, pepper and paprika powder to a meat dough and season to taste.
Shape 10 balls of the same size with wet hands. Heat 2 tablespoons of the oil in the pan and fry the meatballs in it for 10 minutes.
Rub a baking dish (15 x 25 cm) with the cut surfaces of a halved clove of garlic. Roughly dice the flatbread and place in the pan. Roast under the grill at 250 ° C for about 4 minutes.
Mix together yogurt, remaining egg yolk, remaining oil, salt, pepper and chilli flakes. Halve the cherry tomatoes and add to the flatbread cubes with the meatballs. Spread the yogurt sauce over it.
Bake in the preheated oven on the middle rack at 180 ° C (convection 160 ° C) for 15 - 20 minutes. Serve sprinkled with oregano.