Method

For the fish patty

Prepare the fish

Pat the fish fillet dry with paper towels, then cut into roughly 1-inch pieces. Place pieces in a small bowl or on a cutting board.

Season and mix

Sprinkle the fish with 1/2 tsp of the salt and the black pepper. Add the lemon juice, mayonnaise and chopped onion. Break the fish up and gently mash with a fork until it becomes a coarse, slightly sticky mixture leaving some small flakes for texture.

Bind the patty

Add the flour and the beaten egg to the fish mixture. Mix gently until combined; the mixture should hold together when pressed. If too wet, add up to 1 additional teaspoon of flour; if too dry, add a few drops of water or a little more mayonnaise.

Form and chill

Form the mixture into a 1/4‑inch thick patty roughly the diameter of your bun (about 3–4 inches). Place on a plate and chill in the refrigerator for 10 minutes to firm up—this helps it hold together while cooking.

Pan-fry the patty

Heat 2 tablespoons vegetable oil in a nonstick skillet over medium heat until shimmering. Add the patty and cook 3–4 minutes per side, until golden brown and the internal temperature reaches 145°F (63°C) and fish is opaque throughout. If browning too quickly, reduce heat to medium-low. Transfer cooked patty to a paper towel–lined plate to drain any excess oil.

For the sandwich

Prepare the bun by slicing it in half. If desired, spread the inside of each half with the softened butter (this is optional for a plain Fish-Wich).

If you prefer a warm bun, toast the cut sides in a dry skillet or under a broiler for 30–60 seconds until lightly browned.

Place the cooked fish patty on the bottom half of the bun. Top with the other bun half and press gently. Serve immediately while hot.

Fish-wich (1/4 Lb.) Plain Recipe