Peel and finely dice the onion and garlic. Wash the cherry tomatoes and cut into slices. Cut soft tomatoes into short strips. Heat 2 tbsp. oil, fry onion and garlic lightly for about 10 minutes.
After about 4 minutes add soft tomatoes and cherry tomatoes. Season to taste with salt and pepper.
Wash the fish, dab dry and season with salt and pepper. Turn fillets in flour. Heat 2 tablespoons of oil in a large frying pan and fry the fillets for about 4 minutes, turning them over. Dice cheese and stir into the tomato mixture.
Place the fillets in greased ovenproof moulds. Spread tomato mixture on top. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for approx. 10 minutes.
Meanwhile, prepare the pasta in boiling salted water according to the instructions on the packet. Drain the noodles, removing 100 ml of noodle water. Mix pesto and pasta water. Put the noodles back into the pot and stir in the pesto.
Serve fish and pasta.