Peel and finely dice the onions and garlic, fry in hot oil, add the mince and fry through. Season with salt and pepper and season generously with oregano.
Add the chopped tomato pulp, the rice and the stock and let the rice swell a little.
Put everything together in a flat baking dish and bake covered in the oven at 175 degrees for 30 minutes.
Mix the crème fraîche and the grated cheese, season with salt and pepper, add to the casserole and bake for another 15 minutes in the oven without a lid, until the surface is golden yellow.