Cook the pasta in plenty of salted water until al dente. Drain on a sieve. Halve the peppers, clean, wash and cut into small cubes. Cook the peas in boiling salted water. Drain the corn. Then mix all the ingredients together.
For the marinade, peel and finely dice the onions. Mix with vinegar, salt, pepper and sugar, slowly stir in the oil. Pull the marinade into the salad.