Fill a large pot with salted water and bring it to a rolling boil over high heat. Add the spaghetti and cook for 8-10 minutes, or until al dente. Drain and set aside to cool.

Rinse the spaghetti under cold running water to halt the cooking process. Set in a colander to remove excess moisture.

Wash and chop your vegetables. Halve the cherry tomatoes, dice the cucumber and bell peppers, and finely chop the red onion.

In a large mixing bowl, combine the cooled spaghetti and the chopped vegetables. Toss gently to mix.

Pour the Italian dressing over the salad mixture and toss to coat everything evenly.

Season with salt and pepper to taste. Add Parmesan cheese if desired and mix gently.

Refrigerate the salad for at least one hour before serving to enhance the flavors.