Creating Spinach Stuffed Chicken Breast is simple if you follow these easy steps:

1. Preheat Oven: Preheat your oven to 375°F (190°C).
2. Prepare Filling: In a mixing bowl, combine the chopped spinach, cream cheese, mozzarella cheese, Parmesan cheese, minced garlic, onion powder, Italian seasoning, salt, and pepper. Mix until well combined.
3. Prepare Chicken: Use a sharp knife to create a pocket in each chicken breast. Be careful not to cut all the way through.
4. Stuff Chicken: Spoon the spinach filling into each chicken breast pocket. Secure with toothpicks if necessary.
5. Sear Chicken: In an oven-safe skillet, heat olive oil over medium-high heat. Sear the stuffed chicken breasts for about 3-4 minutes on each side until golden brown.
6. Bake: Transfer the skillet to the preheated oven and bake for 20-25 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C).
7. Rest: Remove from the oven and let the chicken rest for a few minutes before serving. This allows the juices to redistribute.
8. Serve: Optionally, remove toothpicks and slice the chicken to reveal the beautiful filling.

Following these steps will guide you in creating this incredible dish effortlessly.