Preheat the oven to 400°F. Pat the chicken thighs dry with paper towels.
Mix the garlic powder, paprika, salt and pepper in a small bowl.
Pile the vegetables on a large rimmed sheet pan. Drizzle with half of the oil, sprinkle with a third of the seasoning and toss to coat. Spread them out.
Rub the chicken with the remaining oil and seasoning. Nestle the thighs among the vegetables, skin side up.
Bake for 40–45 minutes, until the skin is golden and crisp and a thermometer in the thickest part of a thigh reads at least 165°F.
Rest for 5 minutes before serving.