Step 1

Stir egg whites and water together with a fork in a wide, shallow bowl. Mix cornmeal, flour, and pepper together with a fork on a plate.

Step 2

Heat oil in a deep-fryer or large saucepan to 350 degrees F (175 degrees C).

Step 3

Dip each flounder fillet into the egg white mixture and press into the cornmeal mixture to coat completely. Gently toss between your hands so any cornmeal that hasn't stuck can fall away. Place fish onto a plate while preparing the rest of the fillets; do not stack.

Step 4

Carefully put fish into the hot oil and cook until golden brown, 3 to 5 minutes per side. Drain fillets on a plate lined with paper towel; season with salt.