Steps
1. Preheat the oven to 375°F (190°C).
2. Butterfly the chicken breast by making a horizontal cut almost through the thickness, then open it up like a book.
3. In a small bowl, mix together the chopped spinach, feta cheese, minced garlic, olive oil, salt, and pepper.
4. Stuff the spinach and feta mixture into the pocket of the chicken breast.
5. Use toothpicks to secure the opening of the chicken breast.
6. Place the stuffed chicken breast on a baking sheet lined with parchment paper.
7. Bake in the preheated oven for 25-30 minutes, or until the chicken is cooked through and no longer pink in the center.
8. Remove the toothpicks and let the chicken rest for a few minutes before serving.