Place chicken breasts into a large zipper food storage bag or shallow dish/container. Mix 1 cup (240ml) of dressing and Italian seasoning, if using, together and pour on top of chicken. Turn chicken to coat. Seal the bag/cover the dish and refrigerate for 2—24 hours.

Combine the chopped tomatoes, chopped basil leaves, minced garlic, and the remaining 2 Tablespoons of Italian dressing. Add salt and freshly ground pepper to taste. You should end up with about 2 and 1/2 cups (475g) of the bruschetta mixture. Cover tightly and refrigerate for 2—24 hours.

In a large skillet, heat 1 Tablespoon of olive oil over medium heat. Add the marinated chicken (discard marinade), cover, and cook for 10–15 minutes, turning a few times. You want the chicken nice and golden-brown on the outside while fully cooked inside. (Chicken is considered done when an instant read thermometer reads the center of the thickest part as at least 165°F (74°C).) Remove the chicken to a cutting board; do not clean out skillet. Slice the chicken.

Add 1 Tablespoon of olive oil to the skillet, followed by the zucchini noodles (see Notes if using frozen zucchini noodles) and about 1 cup of the bruschetta topping. Cook for 5 minutes, stirring occasionally. The noodles will cook down, absorbing the flavors. Remove from heat and carefully drain off most of the liquid.

Return the skillet to the stovetop, and add the sliced cooked chicken and the remaining bruschetta mixture. Cook, stirring, for about a minute, until warmed through. Serve immediately, topped with grated parmesan cheese and more fresh basil, if desired.

Leftovers keep well in the refrigerator for a few days. Reheat in the microwave or covered on the stove over low heat until warmed.