Using a cast-iron, or heavy bottom skillet, pour oil into skillet and heat to medium;
1½ cups oil
While oil is heating, take a fillet directly from the buttermilk and place it in the cornmeal; pat the cornmeal on the fillet; coat it all over, twice; repeat with remaining fillets
Check your skillet; the oil needs to be around 312 - 350ºF; you can sprinkle a few pieces of cornmeal in the oil to see if it sizzles; if it does sizzle, the oil is ready
Cooking in batches of two fillets, place them in the hot oil; DO NOT MOVE THE FILLETS until they've cooked for 2 1/2 - 3 minutes on one side
After 2 1/2 -3 minutes, use tongs and flip the fish over and cook for an additional 3 minutes
Use a thermometer to measure internal temperature; it should be 145ºF
Remove fillets from oil and place on a paper towel
Repeat until all fillets are cooked and drained
Plate fillets and serve with lemon and tartar sauce
Tartar Sauce Preparation
In a small bowl, combine all ingredients; refrigerate until ready to serve
If using frozen catfish, thaw fish first by rinsing in cold water in a colander or allowing to thaw in the refrigerator
Use a heavy-duty skillet (cast-iron) or Dutch oven
The amount of oil depends upon the size of your skillet; you want about 2" inches of oil
If the oil starts to smoke, turn the heat down and remove the skillet from the burner for a few minutes. After the heat has been reduced, put the skillet back on the burner. Keep an eye on the oil.
Do not move the catfish fillets for the first 3-minutes; if you do, the coating will fall apart. Just stand there and watch...and wait
When flipping the fillets, use tongs or a spider
Your second batch of fillets will be darker than the first; that's because they're being cooked in oil that's already been used. If this really bugs you, throw out the first batch of oil and start over.
Use a thermometer; internal temperature should be 145ºF
Don't have buttermilk?Make your own! Add 1 tablespoon fresh lemon juice to 1 cup of plain milk. Stir it and let it sit for a few minutes at room temperature. Now you have buttermilk!