Cut tomatoes and mozzarella into slices. Cover the bread with them. Season with salt and pepper. Bake in the preheated oven on the highest setting or under the hot grill for 3-4 minutes. Sprinkle basil leaves over it
Or: Season tomatoes with salt, pepper and 1-2 tsp vinegar. Spread on the slice of bread with mozzarella and basil and serve cold