Fish Sandwich Recipe

In a small bowl combine mayonnaise, chopped dill pickle (or relish), chopped capers if using, lemon juice, Dijon mustard and chopped parsley. Stir until smooth.

Season to taste with 1/4 tsp salt and 1/4 tsp black pepper. Refrigerate while preparing fish to allow flavors to meld.

Prepare fish

Pat fish fillets dry with paper towels. Cut into 4 sandwich-sized pieces (about 4 oz each) and season both sides lightly with 1/2 tsp salt and 1/2 tsp black pepper, plus 1/2 tsp paprika.

Optional: panko coating

If using panko for extra crispness, beat 1 egg in a shallow bowl. Place 1/2 cup panko in another shallow bowl. After battering (next steps), dip battered fish briefly into egg then press into panko and set aside.

Make batter

In a medium bowl whisk together 3 tbs flour, 2 tbs cornstarch and 1/2 tsp baking powder. Add about 1/2 cup cold sparkling water (or cold beer) gradually and whisk just until combined into a slightly thick, lumpy batter. Do not overmix. Batter should coat the back of a spoon; add a splash more liquid if too thick. Season batter with a pinch of salt and a grind of pepper.

Heat oil

Pour about 1 cup vegetable oil into a heavy skillet (or 2 cups if using a deep pot) to a depth of roughly 1/2 inch. Heat oil over medium-high heat until it reaches 350°F (175°C) or a small drop of batter sizzles and browns within 20–30 seconds.

Fry fish

Working in batches if needed, dip each seasoned fillet into the batter, letting excess drip off. If using panko, dip battered fillet into beaten egg then press into panko. Carefully place fillet in hot oil. Fry 2–3 minutes per side (depending on thickness) until golden brown and the fish registers 145°F (63°C) or flakes easily. Avoid overcrowding the pan. Transfer cooked pieces to a wire rack or paper towel-lined plate to drain and rest for 1–2 minutes.

Finish

If pieces are uneven, keep finished fish warm in a 200°F (95°C) oven on a tray while frying remaining pieces so sandwiches assemble hot.

Prepare produce: Slice the tomato into 4 even slices. Thinly slice the red onion. Separate and dry 4 lettuce leaves.

Toast buns: Lightly butter the cut sides of the 4 buns (optional) and toast in a skillet or oven until golden, about 1–2 minutes per side. This prevents sogginess.

Assemble sandwiches: Spread about 1½–2 tbs of the prepared tartar-style sauce on the bottom half of each toasted bun. Place a lettuce leaf on the sauce, then one fried fish fillet. Top each fillet with a tomato slice, a few red onion rings and two pickle slices. Spoon another 1 tbs sauce onto the top bun and close sandwich.

Serve: Serve immediately while fish is hot and crisp. Provide extra tartar sauce on the side if desired.