In a large bowl, whisk together the milk, salt, and black pepper. Add the chicken drumsticks, making sure they are fully coated. Cover and refrigerate for at least 2 hours or overnight.
Combine the flour, salt, black pepper, garlic powder, and onion powder in a separate shallow bowl or dish.
Remove each drumstick from the marinade and let any extra liquid drip away. Press the chicken into the flour mixture until evenly coated on all sides.
Heat oil in a deep skillet or heavy pot to 350°F. Fry the drumsticks in batches for 12 to 15 minutes, turning occasionally, until crispy, golden brown, and fully cooked. Let rest briefly before serving.
