Place chicken breasts into a large ziplock bag or shallow tupperware. Pour 1 cup of dressing on top and make sure it covers every inch of chicken. Seal up and refrigerate for 2 - 24 hours. 8 hours allows for the best flavour.
Make the bruschetta topping by combining the chopped tomatoes, basil leaves, minced garlic, and 2 tablespoons remaining Italian dressing. Add salt and freshly ground pepper to taste. 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 and cook for 15 minutes, turning once. You want the chicken nice and browned on the outside while fully cooked inside. Remove the chicken from the skillet; do not clean out skillet.
Add 1 tablespoon of olive oil to the skillet, followed by the zucchini noodles and 3/4 cup of the bruschetta topping. Cook for 5-6 minutes, stirring occasionally. The noodles will cook down, absorbing all the flavour.
Remove from heat and place chicken on top of the noodles– or, if using a serving dish, place noodles on first and top with chicken.
Evenly top each chicken breast with remaining bruschetta mixture.
Serve immediately and enjoy!