Into a mixing bowl, add All-Purpose Flour (1/2 cup), Corn Starch (1/4 cup), Baking Powder (1/2 teaspoon), Granulated Sugar (1/2 teaspoon), Salt (1/4 teaspoon), and Ground Black Pepper (1/4 teaspoon). Mix to combine.
Add ice cold Water (1/2 cup). Whisk until mixture comes together into a batter.
Dip Flounder Fillet (8) into the batter to coat.
In a skillet, heat Cooking Oil (as needed). Add flounder fillets and fry until golden brown, about 3-4 minutes on each side. Remove finished fillets to a plate lined with paper towels to drain excess oil.
Serve warm with sauces of choice!