Filet O' Fish Sandwich Recipe

Prepare fish

Pat the cod fillets dry with paper towels. Trim to roughly uniform thickness if needed so pieces cook evenly. Season both sides lightly with 1 tsp of the salt and 1/4 tsp of the black pepper.

Make batter

In a mixing bowl, whisk together the 1 cup all-purpose flour, 1/4 cup cornstarch, 1 tsp baking powder and remaining 1/2 tsp salt. In a separate small bowl, beat the egg and combine with the cold beer. Pour the wet mixture into the dry ingredients and whisk just until combined; small lumps are fine. Batter should be thick enough to cling to the fish but still pourable; add a tablespoon of cold beer or flour to adjust consistency if needed. Keep batter cold (place bowl in an ice bath) until ready to use.

Dredge & fry

Fill a deep, heavy pot or deep-fryer with enough vegetable oil to submerge the fillets (about 3–4 inches deep). Heat oil to 350°F (175°C). Place the 1 cup flour for dredging on a shallow plate and season very lightly (a pinch of salt and pepper). Dredge each seasoned fillet in the flour, shaking off excess, then immediately dip into the cold beer batter, coating completely. Carefully lower battered fillet into the hot oil, two at a time depending on pot size, and fry until golden brown and the internal temperature reaches 145°F (about 3–5 minutes per side depending on thickness). Remove with a slotted spoon or spider and drain on a wire rack set over a sheet pan or on paper towels. Keep cooked fillets warm in a 200°F (95°C) oven while frying remaining fish.

While the fish fries, combine 1/2 cup mayonnaise, 2 tbsp finely minced dill pickle or 2 tbsp sweet relish, 1 tsp chopped capers (if using), 1 tsp fresh lemon juice, 1/2 tsp mustard, 1 tsp chopped parsley, 1/4 tsp salt and 1/4 tsp black pepper in a small bowl. Mix thoroughly, taste, and adjust seasoning or lemon to preference. Refrigerate until ready to assemble; flavors meld if made 15–30 minutes ahead.

Toast buns: Heat a skillet over medium heat. Spread softened butter on the cut sides of the 4 buns. Toast cut-side down in the skillet until golden and slightly crisp, about 1–2 minutes. Keep warm.

Assemble sandwiches: On the bottom half of each toasted bun spread about 1–2 tablespoons of tartar sauce. Place one hot fried cod fillet on top of the sauce. Immediately lay one slice of American cheese over the hot fish so it softens/melts slightly. Top with about 1/2 cup shredded iceberg lettuce (approximately 2 cups divided among 4 sandwiches). Spread a thin layer of tartar sauce on the top bun (optional), place the top bun, and serve hot with lemon wedge on the side.

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