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

1. Preheat Oven: Preheat your oven to 375°F (190°C).
2. Prepare Chicken: Using a sharp knife, create a pocket in each chicken breast by slicing horizontally, being careful not to cut all the way through.
3. Make Filling: In a mixing bowl, combine the chopped spinach, cream cheese, mozzarella cheese, minced garlic, onion powder, Italian seasoning, salt, and pepper. Mix until well combined.
4. Stuff Chicken: Generously spoon the spinach mixture into each chicken breast pocket. Secure with toothpicks if needed.
5. Sear Chicken: In an oven-safe skillet, heat olive oil over medium-high heat. Add the stuffed chicken breasts and sear for 3-4 minutes on each side until golden brown.
6. Bake Chicken: Transfer the skillet to the preheated oven and bake for 20-25 minutes, or until the chicken is cooked through (internal temperature should reach 165°F or 75°C).
7. Optional Topping: If desired, sprinkle grated Parmesan cheese on top during the last few minutes of baking for a deliciously cheesy crust.
8. Rest: Once done, remove the skillet from the oven and let the chicken rest for 5 minutes before serving.
9. Slice and Serve: Carefully remove toothpicks and slice the chicken for serving.

These steps will guide you in creating this incredible dish effortlessly.