1. Pat the chicken thighs dry with paper towels. In a medium bowl, toss the chicken thighs with olive oil, dried rosemary, garlic powder, onion powder, salt, and black pepper until evenly coated.

2. Heat a large, oven-safe skillet over medium-high heat. Once hot, add the seasoned chicken thighs to the pan in a single layer. Sear for 5-7 minutes per side, until deeply golden brown and a good crust has formed.

3. Once the chicken is seared, scatter the trimmed green beans around the chicken in the skillet. Pour the apple cider over the chicken and green beans. Bring the liquid to a gentle simmer.

4. Carefully transfer the skillet to a preheated oven at 375 F (190 C). Bake for 15-20 minutes, or until the chicken is cooked through (an internal temperature of 165 F / 74 C) and the green beans are tender-crisp.

5. Remove the skillet from the oven. Carefully transfer the chicken and green beans to a serving platter. Place the skillet back on the stovetop over medium heat. Add the butter to the pan juices. If you want a thicker sauce, whisk in the flour and cook for 1-2 minutes, stirring constantly, until the sauce thickens slightly. If not thickening, simply let the butter melt and combine with the pan juices.

6. Spoon the warm apple cider sauce over the chicken and green beans. Garnish with fresh rosemary sprigs, if desired. Serve immediately and enjoy!