In a large bowl, combine olive oil, garlic powder, onion powder, thyme, rosemary, paprika, salt, and pepper to create a marinade.
Add the chicken thighs to the marinade, ensuring they are well-coated. Allow to marinate for at least 30 minutes, or up to 2 hours in the refrigerator for enhanced flavors.
While the chicken is marinating, prepare the vegetables. In another bowl, toss the halved baby potatoes with a tablespoon of olive oil, salt, and pepper.
Spread the potatoes on a baking sheet in a single layer and roast in the preheated oven for 15 minutes.
After 15 minutes, remove the baking sheet, and add the marinated chicken thighs to the sheet, skin-side up.
Return the baking sheet to the oven and roast for an additional 25 minutes.
In the last 10 minutes of cooking time, add the green beans to the baking sheet, tossing them with the drippings from the chicken and potatoes.
Once the chicken reaches an internal temperature of 165°F (74°C) and the potatoes are golden brown, remove from the oven.
Let the chicken rest for 5 minutes before serving. Garnish with fresh parsley and enjoy your meal!