In a large bowl, soak the shrimp in buttermilk for at least 30 minutes to enhance flavor and tenderness.
In a separate bowl, combine the flour, garlic powder, onion powder, paprika, cayenne pepper, salt, and black pepper. Mix well to ensure even seasoning.
Heat about 2 inches of vegetable oil in a deep skillet or pot over medium-high heat until it reaches 350°F.
Remove the shrimp from the buttermilk, allowing excess to drip off. Dredge each shrimp in the seasoned flour mixture, ensuring they are well-coated. Shake off any excess flour.
Carefully place the coated shrimp in the hot oil, working in batches to avoid overcrowding. Fry for 2-3 minutes or until golden brown and cooked through.
Use a slotted spoon to transfer the shrimp to a paper towel-lined plate to drain excess oil.
Serve immediately with your favorite dipping sauce, such as cocktail sauce or remoulade.