2 1/2 cups buttermilk
2 1/4 pounds fish fillets (6 ounce each)
Vegetable oil
3/4 cup self-rising flour
3/4 cup yellow cornmeal
1 1/2 teaspoons onion salt

Place buttermilk in medium mixing bowl. Add fish. Stir to coat. Cover with plastic wrap. Chill 45 minutes.
In deep-fat fryer, heat 2 inches of oil to 375 degrees. In shallow dish, combine flour, cornmeal, and onion salt. Drain and discard buttermilk from fish pieces. Dredge fish in flour mixture to coat.
In hot oil, fry fish, a few pieces at a time, for 3 to 4 minutes, or until golden brown, turning over once. Drain on paper towel lined plate. Serve with tartar sauce, cocktail sauce, sweet and sour sauce or salsa if desired.
***You may substitute all purpose flour for self rising flour by adding 1 1/2 teaspoons baking powder and 1/2 teaspoon salt***