Steps
1. Preheat oven to 375°F (190°C).
2. In a small bowl, mix mozzarella, cream cheese, chopped spinach, and minced garlic.
3. Cut a pocket into the side of the chicken breast without cutting all the way through.
4. Stuff the cheese and spinach mixture into the pocket.
5. Secure with toothpicks if necessary.
6. Season the chicken with salt and pepper.
7. Heat olive oil in an oven-safe skillet over medium heat.
8. Sear the chicken breast for 3-4 minutes on each side until golden brown.
9. Transfer skillet to the oven and bake for 15-20 minutes until chicken is cooked through.
10. Remove toothpicks before serving.