Preheat the oven: Set to 425°F (220°C). Place a rack in the center.
Line a sheet pan with foil for easy cleanup and set a wire rack on top if you have one.
Prep the chicken: Pat the thighs very dry with paper towels. This step is key. Dry skin equals crisp skin.
Mix the seasoning: In a small bowl, combine salt, pepper, garlic powder, onion powder, smoked paprika, dried thyme, and baking powder.
Oil and season: Rub the thighs with olive oil.
Sprinkle the seasoning mix evenly on all sides, focusing on the skin. Press gently so it sticks.
Arrange for airflow: Place the thighs skin-side up on the wire rack or directly on the lined sheet pan. Leave space between pieces so the hot air can circulate.
Bake until crisp: Cook for 30–40 minutes, depending on size.
The skin should be deep golden and crackly. An instant-read thermometer should read 165°F (74°C) in the thickest part, not touching bone.
Optional broil: For extra crispness, broil on high for 1–2 minutes. Watch closely to prevent burning.
Rest and serve: Let the chicken rest 5 minutes.
Sprinkle with fresh parsley and serve with lemon wedges if you like.