Preheat your oven to 400 degrees Fahrenheit.
In a bowl, mix together the olive oil, garlic, onion, green bell pepper, celery, parsley, salt, and pepper.
Slice the chicken breast down the center on the side, but do not cut all the way through. Open the chicken breast and place the provolone cheese and sun-dried tomatoes in between the breast.
Once the chicken is stuffed, add the vegetable and herb mixture on top of the chicken breast.
Place the chicken breast on a lined baking sheet and bake in the preheated oven for about 25-35 minutes, depending on the size of the breast.
Once the chicken is cooked through and the juices run clear, remove it from the oven and let it rest for a few minutes before slicing and serving with your desired sides.
