Fish Sandwich Recipe

In a small bowl combine mayonnaise, chopped dill pickles or relish, lemon juice, chopped capers (if using), and chopped parsley. Season with 1/4 tsp salt and 1/4 tsp black pepper. Stir until smooth, taste and adjust seasoning. Refrigerate while you prepare the fish so flavors meld.

Prep the fish

Pat fish fillets dry with paper towels. Cut into portions about 4–5 ounces each (to fit buns). Lightly season both sides with 1/2 tsp salt and 1/2 tsp black pepper.

Make the batter

In a medium bowl whisk together 1/2 cup all-purpose flour, 1/4 cup cornmeal and 1 tsp baking powder. In a separate small bowl beat the egg, then whisk in 3/4 cup cold sparkling water or beer. Pour the wet into the dry and whisk until just combined; batter should be slightly thick but still runny enough to coat (adjust with a tablespoon of water if too thick). Keep batter cold — place bowl in a larger bowl with ice if necessary.

Dredge and fry

Heat 1 cup vegetable oil in a large skillet over medium-high until shimmering and a small drop of batter sizzles immediately (about 350°F/175°C). Lightly dredge each seasoned fillet in the 1/2 cup flour (shake off excess), then dip into the batter to coat completely. Carefully place fillets into hot oil, leaving space between pieces. Fry 3–4 minutes per side or until golden brown and internal fish temperature reaches 145°F/63°C. Work in batches to avoid overcrowding. Transfer cooked fillets to a rack or paper towel-lined plate and keep warm in a low oven (200°F/95°C) while frying remaining pieces.

Optional crisp finish

If you prefer an extra-crisp exterior, after initial frying for 3–4 minutes per side, increase heat briefly and fry each piece 30–45 seconds more until deeply golden, then drain as above.

Toast the buns: spread softened butter on cut sides of the 4 buns and toast in a skillet or under a broiler until lightly golden, about 1–2 minutes per side.

Assemble sandwiches: spread about 1 to 1 1/2 tablespoons of the tartar-style sauce on the bottom of each toasted bun. Place a lettuce leaf on each bottom bun, top with a hot battered fish portion, add 2–3 tomato slices and 2–3 pickle slices. Spoon additional sauce on the top bun if desired. Close sandwiches and serve immediately.

Serve suggestions and storage: Serve hot with lemon wedges, fries or coleslaw. Leftover fish is best eaten within a day—reheat in a 375°F/190°C oven for 8–10 minutes to restore crispness; sauce keeps refrigerated up to 3 days.