01 - Preheat the oven to 400°F. Lightly grease a baking dish and set aside.
02 - Heat 1 tablespoon olive oil in a skillet over medium heat. Sauté minced garlic for 30 seconds until fragrant, then add chopped spinach and cook until wilted, about 2 minutes. Remove from heat and allow to cool slightly.
03 - In a mixing bowl, combine the sautéed spinach with feta cheese, cream cheese, sun-dried tomatoes if using, parsley, and oregano. Stir until thoroughly blended.
04 - Pat chicken breasts completely dry. Using a sharp knife, cut a horizontal pocket into each breast, taking care not to slice through the opposite side.
05 - Season both sides of each breast with salt and black pepper. Generously fill each pocket with the spinach-feta mixture. Secure openings with toothpicks if necessary to prevent filling from escaping.
06 - Arrange the stuffed breasts in the prepared baking dish. Drizzle with remaining olive oil and sprinkle paprika evenly over the top.
07 - Bake for 25 to 30 minutes, or until chicken is cooked through and juices run clear. Internal temperature should reach 165°F.
08 - Allow the chicken to rest for 5 minutes. Remove all toothpicks before plating and serving.