Preheat the oven to 425°F (220°C).
In a large bowl, toss the halved baby potatoes with 1 tablespoon of olive oil, 1/2 teaspoon salt, 1/4 teaspoon black pepper, and half of the garlic powder and smoked paprika.
Spread the potatoes evenly on one side of a large sheet pan.
In the same bowl, toss the green beans with 1 tablespoon of olive oil, 1/4 teaspoon salt, and 1/4 teaspoon black pepper.
Arrange the green beans on the other side of the sheet pan, leaving space for the chicken.
Pat the chicken thighs dry with paper towels. In the bowl, combine the remaining 1 tablespoon olive oil, 1/2 teaspoon salt, 1/4 teaspoon black pepper, remaining garlic powder, smoked paprika, and dried thyme.
Rub the seasoning mixture all over the chicken thighs, including under the skin if possible.
Place the chicken thighs skin-side up on the sheet pan between the potatoes and green beans.
Place the sheet pan in the preheated oven and roast for 30 to 35 minutes, or until the chicken reaches an internal temperature of 165°F (74°C) and the potatoes are tender.
If desired, broil for 2-3 minutes at the end to crisp the chicken skin further, watching carefully to prevent burning.
Remove the sheet pan from the oven and let the chicken rest for 5 minutes.
Serve the chicken thighs with roasted potatoes and green beans, garnished with lemon wedges.