Prep the oven and pan: Preheat your oven to 400°F (200°C). Set a large oven-safe skillet on the stove. If you don’t have one, you can transfer to a baking dish later.

Wilt the spinach: Heat 1 tablespoon olive oil over medium heat. Add spinach and a pinch of salt. Cook 1–2 minutes until wilted. If using frozen spinach, skip cooking and just squeeze out excess moisture well.

Make the filling: In a bowl, combine warm spinach, feta, cream cheese or Greek yogurt, minced garlic, lemon zest, oregano, and a few grinds of pepper. Stir until creamy. Taste and adjust salt—remember feta is salty.

Butterfly the chicken: Place a chicken breast on a cutting board. Using a sharp knife, slice horizontally to create a pocket, stopping about 1/2 inch from the opposite side. Don’t cut all the way through. Repeat with remaining breasts.

Season the chicken: Pat dry with paper towels. Rub both sides with 1–2 tablespoons olive oil, salt, pepper, and smoked paprika if using.

Stuff the pockets: Spoon the spinach-feta mixture evenly into each chicken pocket. Don’t overfill. Secure openings with toothpicks or tie gently with kitchen twine.

Sear for color: Heat the skillet over medium-high with a light drizzle of oil. Sear chicken 2–3 minutes per side until golden. Work in batches if needed to avoid crowding.

Finish in the oven: Transfer the skillet to the oven and bake 12–16 minutes, depending on thickness, until the internal temperature reaches 165°F (74°C) at the thickest part.

Rest and serve: Let the chicken rest 5 minutes. Remove toothpicks or twine. Squeeze with lemon and sprinkle fresh herbs. Serve with your favorite sides.