Place a rack in the center of your oven and preheat the oven to 375 degrees F.
Season the chicken 3/4 teaspoon salt and 1/4 teaspoon black pepper, sprinkling both sides.
In a large, heavy-bottomed, and ovenproof skillet, heat 1 tablespoon olive oil over medium high. Once hot, add the chicken breasts, top side down, and let cook undisturbed for 2 to 3 minutes, until the surface is golden brown. Flip and brown the other side. Remove to a plate (the chicken does not need to be cooked through).
Reduce the heat to medium. Add the remaining 1 tablespoon oil, onion, and remaining ¼ teaspoon salt and ¼ teaspoon black pepper. Sauté until the onion is tender, about 5 minutes.
Add the garlic, Italian seasoning, and red pepper flakes. Let cook until very fragrant, about 30 seconds.
Pour in the pasta sauce and Worcestershire sauce. Let simmer for 5 minutes.
Place the skillet in the oven and cook for 15 to 20 minutes, or until a thermometer inserted in the thickest portion of the chicken registers 165 degrees F and the juices run clear (my smaller breasts were done closer to the 15-minute mark; larger ones may need longer).
Sprinkle with fresh basil and enjoy hot.
TO STORE: Refrigerate leftovers in an airtight storage container for up to 3 days.
TO REHEAT: Rewarm pizza chicken in a skillet on the stovetop over medium-low heat.
TO FREEZE: Freeze leftovers in an airtight freezer-safe storage container for up to 3 months. Let thaw overnight in the refrigerator before reheating.