Preheat your oven to 425°F (220°C).
Soak the chicken thighs in buttermilk for at least 30 minutes.
In a separate bowl, mix flour, garlic powder, onion powder, paprika, salt, and pepper.
Remove chicken from buttermilk and let excess drip off.
Dredge each thigh in the flour mixture, ensuring an even coating.
Place the coated chicken on a baking sheet lined with parchment paper.
Spray the chicken generously with cooking spray or drizzle with olive oil.
Bake in the preheated oven for 35-40 minutes until golden brown.
Broil on high for the last 2-3 minutes for extra crispiness.
Let the chicken rest for a few minutes before serving.