Prep the oven and pan: Preheat the oven to 400°F (200°C). Lightly grease a baking dish or line it with parchment.

Prep the broccoli: If using fresh broccoli, blanch it in boiling water for 1 minute, then drain and chop finely. If using frozen, thaw and pat dry before chopping. Finely chopped pieces help the filling tuck in neatly.

Make the filling: In a bowl, mix the broccoli, shredded cheddar, cream cheese, garlic, Dijon (if using), onion powder, and a generous pinch of salt and pepper. Stir until creamy and evenly combined.

Butterfly the chicken: Place a hand flat on each chicken breast and slice horizontally to create a pocket without cutting all the way through. Open it like a book. Pat dry with paper towels.

Season the outside: In a small dish, combine paprika, thyme, 1 teaspoon salt, and 1/2 teaspoon black pepper. Rub olive oil over the chicken, then sprinkle the seasoning on both sides.

Stuff and secure: Divide the filling among the chicken breasts and fold them closed. Secure edges with toothpicks to keep the filling inside. Don’t overstuff; a little room helps it seal.

Sear for extra flavor (optional but recommended): Heat a skillet over medium-high. Sear the stuffed chicken for 2–3 minutes per side until lightly browned. Transfer to the baking dish.

Bake until done: Bake for 18–22 minutes, or until the thickest part reaches an internal temperature of 165°F (74°C). Rest for 5 minutes so the juices settle.

Serve: Remove toothpicks. Slice and plate with a squeeze of lemon and your favorite sides. Roasted potatoes, rice, or a crisp salad work well.