Pat the chicken thighs dry with a clean towel and rub them with 1 teaspoon salt, 1/2 teaspoon pepper, garlic powder, and smoked paprika. Let them rest while you prep the potatoes.

Preheat your oven to 425°F (220°C). Place a large cast-iron skillet on the stove over medium-high heat and add 2 tablespoons olive oil.

Sear the chicken thighs skin-side down in the hot skillet for about 6–8 minutes until the skin is deeply golden and releases easily from the pan. Flip and sear the other side for 2–3 minutes. Remove the chicken from the pan and set aside.

Meanwhile, parboil the potatoes: place them in a pot, cover with salted water, and boil until just tender, about 8–10 minutes. Drain and let them cool slightly.

Gently smash each potato to about 1/2-inch thick. Place them in a single layer on a parchment-lined baking sheet. Drizzle with 3 tablespoons olive oil, sprinkle with salt, pepper, and minced garlic. Toss to coat, then spread in a single layer.

Return the skillet to the oven with the chicken in it (you can nestle the chicken back into the pan after smashing the potatoes if there’s space). Roast for 20–25 minutes, until the potatoes are crisp around the edges and the chicken reaches an internal temperature of 165°F (74°C). If you prefer extra crispiness, broil for 1–2 minutes at the end, watching closely.

Finish with a quick butter glaze if you like: remove from the oven, spoon a teaspoon of butter over the chicken and let it melt into the skin for added richness.

Garnish with a fresh rosemary sprig (if using) and serve immediately, pairing the juicy chicken with the crisp smashed potatoes for a balanced bite.