Put the pasta in boiling salted water and cook for about 12 minutes. Cut tomatoes crosswise, dip briefly into boiling water, peel skin. Cut tomatoes into quarters, remove seeds and cut into cubes.
Heat peas and diced tomatoes in the broth and season with salt, pepper and sherry. Drain the noodles and add to the soup. Wash the chives, cut them into fine rolls and sprinkle over them.