01 - Preheat the oven to 400°F. Lightly grease a baking dish with cooking spray or a small amount of olive oil.
02 - In a mixing bowl, combine crumbled feta cheese, chopped spinach, minced garlic, cream cheese, fresh dill, salt, and black pepper. Mix thoroughly until evenly blended and creamy.
03 - Using a sharp knife, slice a horizontal pocket into each chicken breast, being careful not to cut completely through. Open gently to create space for the filling.
04 - Generously fill each pocket with the spinach and feta mixture. Secure openings with toothpicks to prevent filling from escaping during cooking.
05 - Rub the exterior of each stuffed breast with olive oil. Season generously with additional salt and freshly ground black pepper on all sides.
06 - Place the stuffed chicken breasts in the prepared baking dish, spacing them evenly to ensure proper heat circulation.
07 - Bake for 25 to 30 minutes, or until the chicken is completely cooked through and the juices run clear when pierced. The internal temperature should reach 165°F.
08 - Carefully remove toothpicks before serving. Plate the chicken breasts and garnish with fresh lemon wedges on the side.