Cook the pasta in boiling salted water according to the instructions on the packet. Wash tomatoes, grate dry, cut off lid. Hollow out the tomatoes. Chop tomatoes inside. Peel onion and cut into small cubes.
Pour hot water over peas and drain. Cut mozzarella into small cubes. Drain tuna. Wash basil, dab dry and chop the leaves of 3 stems. Drain the pasta and let it drain. Heat the oil in a pan. Sweat onion cubes for 1-2 minutes, then add noodles and peas. After 3-4 minutes add tuna, tomato interior and juice and bring to the boil. Finally add mozzarella and basil and season with salt and pepper.
Heat the oil in a pan. Sweat onion cubes for 1-2 minutes, then add noodles and peas. After 3-4 minutes add tuna, tomato interior and juice and bring to the boil. Finally add mozzarella and basil and season with salt and pepper. Season tomatoes inside with salt and pepper, then add the pasta mix. Put the tomatoes into a casserole dish and bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 15 minutes