Smear a fire-proof dish with a little oil. Preheat the oven to 220 ° C.
Wash the tomatoes, dry them and cut them into 1 cm thick slices with the cheese.
Peel and finely dice the onions and the clove of garlic. 4 tablespoon
Heat olive oil in a pan and sauté the onions and garlic for a few minutes until translucent. Season well with pepper, salt and thyme.
Layer the tomato slices like a roof tile in the ovenproof dish. Spread the onion and garlic mixture over it. Spread the cheese slices over the top and bake in the preheated oven on the middle rack for 25 minutes.