11. Preheat broiler to high.
2. Heat a saucepan over medium-high heat and coat the pan with cooking spray. Add garlic and pepperoni chunks; stirring frequently cook for 2 minutes or until garlic begins to brown.
3. Stir in oregano and stir for 30 seconds. Add marinara sauce and bring to a boil. Reduce heat and simmer for 5 minutes. Remove from heat and stir in chopped basil. Set sauce aside.
4. Heat a large ovenproof skillet over medium-high heat and coat with olive oil. Season chicken with salt and pepper. Place chicken in the skillet and cook for about 5-10 minutes (depending on if you're using frozen or thawed) or until lightly browned turning chicken half-way through.
5. Spoon sauce over the chicken and sprinkle mozzarella cheese. Place in broiler until cheese melts. Remove and garnish with additional basil leaves (optional