Prep the chicken. Pat the chicken dry with paper towels. Dry skin helps it crisp.
Season both sides with salt and pepper.
Make the marinade. In a bowl, combine zest of 1 lemon, juice of 1 lemon, 2 tablespoons olive oil, minced garlic, and chopped rosemary leaves. Add a pinch of red pepper flakes if you like heat.
Marinate briefly. Toss the chicken in the marinade until well coated. Let it sit 20–30 minutes at room temperature or up to 8 hours in the fridge. Don’t skip the zest; it delivers a lot of lemon flavor.
Preheat and set up. Heat the oven to 400°F (200°C).
Place an oven-safe skillet (cast iron is ideal) on medium-high heat and add 1 tablespoon olive oil.
Sear the chicken. Place the chicken skin-side down. Cook without moving for 4–6 minutes until the skin is deeply golden and crisp. Flip and sear the other side for 2–3 minutes.
Roast to finish. Slide the skillet into the oven and roast 12–18 minutes, depending on thickness, until the internal temperature reaches 165°F (74°C).
Rest the chicken. Transfer to a plate and tent loosely with foil for 5–7 minutes.
Resting keeps it juicy.
Make a quick pan sauce. Return the skillet to medium heat. Add chicken broth, scraping up the browned bits. Simmer 2–3 minutes to reduce slightly.
Whisk in 1 tablespoon butter and a squeeze of lemon. Optional: add 1 teaspoon Dijon or 1 tablespoon honey for balance.
Serve. Spoon the sauce over the chicken. Garnish with extra rosemary and lemon slices.
Pair with roasted potatoes, steamed green beans, or a peppery arugula salad.