In a large bowl, combine the chicken, veggies, and pesto until the chicken and veggies are coated well with pesto.
Transfer mixture to a large sheet pan and bake for 15-20 minutes. If desired drizzle with mozzarella cheese during the last 5 minutes of baking.
Make-ahead and Storing Instructions:You can prep the pesto chicken up to 1 day ahead of time and let it sit in the refrigerator until ready to bake. Store leftovers in an airtight container in the refrigerator for 3-4 days.