Cook the pasta in boiling salted water for about 10 minutes. Meanwhile wash the rocket and cut off the stalks if necessary. Wash and halve the tomatoes. Clean and wash spring onions and cut them into rings. Quarter peppers, remove seeds, wash and cut into pieces.
Drain noodles, quench briefly and let drain. Mix vinegar, broth and mustard. Gradually add the oil. Season with salt, pepper and 1 pinch of sugar. Mix the lukewarm pasta, rocket, tomatoes, spring onions and peppers with the vinaigrette and arrange on plates.