Preheat oven to 400 degree F. Line a baking sheet with parchment paper.
Combine balsamic vinegar, olive oil, garlic, basil, thyme, salt, and pepper. Whisk to make sauce.
Place chicken in zip-lock bag with about 1/3 cup of the balsamic sauce. Set in fridge.
Meanwhile, chop veggies.
Place veggies, EXCEPT tomatoes, on the sheet pan. Pour remaining balsamic sauce over veggies and toss veggies to coat. Make sure all pieces are coated.
Remove chicken from zip-lock bag, move veggies around to make space for the chicken. Place chicken on pan.
Transfer pan to the oven and bake for 10 minutes. After 10 minutes, remove from oven and add tomatoes and toss veggies. Place back in the oven.
Bake for an additional 5-10 minutes or until chicken is cooked through. This will depend on the thickness of the chicken. To ensure chicken is done, you could use a meat thermometer. Once thermometer reaches 165 degrees F, remove pan from oven.