Wash the meat, dab dry and season with salt and pepper. Heat oil in portions in a coated pan. Fry the meat for about 2 minutes, turning it over. In the meantime, cut the mozzarella into 16 slices.
Clean, wash and cut the tomatoes into 8 slices. For the pesto basil, wash, shake dry, pluck leaves from the stalks. Put basil, pine nuts, 4-5 tablespoons of water and olive oil into a tall mixing bowl.
Finely puree with a blender. Season to taste with salt and pepper. Place steaks with frying set in 2 casseroles or in the fat pan of the oven. Spread the steaks with pesto and cover with 2 slices of tomato and mozzarella.
Gratinate the steaks in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 5 minutes, remove. Garnish with basil leaves if necessary. Ciabatta bread tastes good with it.