Rinse the chicken drumsticks under cold water and pat them dry with paper towels.
Place the drumsticks in a large bowl and pour the buttermilk over them. Add half of the salt and pepper, ensuring the chicken is fully coated. Cover the bowl and refrigerate for at least 2 hours to marinate.
In a separate bowl, combine the flour, paprika, garlic powder, onion powder, and the remaining salt and pepper. Mix well to create a seasoned flour coating.
Remove the chicken from the buttermilk, allowing any excess liquid to drip off. Roll each drumstick in the seasoned flour, pressing the mixture firmly onto the chicken to create a thick, even coating.
Heat vegetable oil in a deep fryer or large, heavy-bottomed pot to 350–375°F.
Carefully place a few drumsticks at a time into the hot oil, being careful not to overcrowd the fryer. Fry the chicken for 12–15 minutes, turning occasionally, until it is golden brown, crispy, and cooked through. The internal temperature should reach 165°F.
Use a slotted spoon to remove the chicken from the oil and place it on a plate lined with paper towels to drain any excess grease.
Allow the chicken to cool slightly before serving. Pair with your favorite sides and enjoy this crispy, flavorful buttermilk fried chicken!