Wash tomatoes, remove seeds and stalks and cut into small cubes. Chop basil. Preheat oven to 200° C.
Put filets on the bride side of aluminium foil, cover with tomatoe cubes and basil and sprinkle with olive oil. Close foil well and cook all in oven for about 10 minutes.
Marinade salad with lemon juice, some olive oil and season to taste with salt and pepper.
Remove filets from oven, open foil and spice with salt.
Serve with salad.