Preheat your oven to 400°F (200°C).
In a mixing bowl, combine the ranch dressing mix, garlic powder, onion powder, smoked paprika, black pepper, and salt.
Pat the chicken thighs dry with paper towels to ensure crispiness.
Drizzle the olive oil over the chicken thighs, turning them to coat evenly.
Sprinkle the ranch seasoning mixture over the chicken thighs, making sure to coat both sides well.
Place the seasoned chicken thighs skin-side up in a baking dish.
Bake in the preheated oven for approximately 30 minutes, or until the chicken reaches an internal temperature of 165°F (75°C) and the skin is golden brown.
If desired, switch to broil for the last 3-5 minutes to crisp the skin further.
Remove from the oven and let the chicken rest for 5 minutes before serving.
Garnish with fresh parsley if desired.