Preheat the oven to 425°F (220°C). Pat the chicken thighs dry with paper towels and place them in a large bowl.
In a small bowl whisk together olive oil, melted butter, minced garlic, lemon juice, paprika, garlic powder, onion powder, salt and pepper.
Pour the mixture over the chicken and toss to coat evenly. Let sit for 10 minutes to absorb flavors (or refrigerate up to 2 hours).
Arrange the thighs skinless side up on a rimmed baking sheet or in a shallow roasting pan, spaced slightly apart.
Roast in the preheated oven for 30–35 minutes, until an instant-read thermometer inserted into the thickest part reads 165°F and juices run clear. For a slightly crisp exterior, broil 2–3 minutes at the end, watching closely.
Remove from oven and let rest 5 minutes. Sprinkle with chopped parsley before serving.
Notes
Serve with mashed potatoes or a simple salad. Leftovers keep well in the fridge for 3 days.