01 - Preheat oven to 400°F. Line a baking sheet with parchment paper or lightly grease with oil.
02 - In a small bowl, mix garlic powder, paprika, salt, and black pepper until combined.
03 - Pat chicken breasts dry. Using a sharp knife, cut a deep pocket into each breast without slicing through.
04 - Rub each chicken breast with olive oil, then coat evenly with the seasoning mixture, including inside the pockets.
05 - In a separate bowl, mix broccoli, shredded cheddar, cream cheese, Parmesan, Dijon mustard, and minced garlic until thoroughly incorporated.
06 - Fill each chicken breast pocket with the broccoli-cheese mixture, securing with toothpicks as needed to hold the filling.
07 - Place the stuffed chicken breasts on the prepared baking sheet. Bake for 25 to 30 minutes, or until chicken reaches an internal temperature of 165°F and cheese is bubbling.
08 - Allow chicken to rest for 5 minutes before serving. Remove toothpicks carefully before plating.