Fish Sandwich On A Sub Bun Recipe

Prepare and marinate

Pat fish fillets dry with paper towels and cut into sandwich-appropriate portions (2 equal pieces for 2 sandwiches). Place fish in a shallow bowl, drizzle with lemon juice, then sprinkle salt, black pepper, and garlic powder. Rub gently to coat and let sit at room temperature for 10 minutes while you prepare the breading.

Set up breading stations

In three shallow bowls or plates, place: 1) flour mixed with cornstarch, paprika, onion powder, 0.5 tsp salt and 0.25 tsp pepper; 2) beaten eggs whisked with milk (or water) until smooth; 3) panko mixed with dry breadcrumbs (if using).

Coat the fish

Working one piece at a time: dredge fish in the flour mixture, shaking off excess; dip into the egg wash allowing excess to drip off; press firmly into the panko mixture to fully coat. Place coated pieces on a wire rack while you heat the oil. If time permits, rest the coated fish for 5–10 minutes to help the coating adhere.

Heat oil

Pour oil into a heavy skillet (cast-iron or stainless) to a depth of about 1/3 inch (or use enough for shallow frying). Heat over medium-high until oil registers 350°F (175°C) or a small breadcrumb sizzles and browns in about 30–45 seconds.

Fry the fish

Carefully add coated fish pieces to the hot oil, leaving space between them. Fry 3–4 minutes per side (depending on thickness) until golden brown and internal temperature reaches 145°F (63°C) or the flesh flakes easily. Adjust heat to maintain temperature; avoid overcrowding. Transfer cooked fish to a paper towel–lined rack or plate to drain; keep warm in a low oven (200°F / 95°C) if making both at once.

Make the sandwich sauce

In a small bowl combine mayonnaise, yellow mustard, sweet pickle relish, and hot sauce (if using). Taste and adjust seasoning. This yields a tangy, slightly sweet sandwich sauce.

Prepare vegetables

Slice tomato into 1/4-inch thick rounds. Thinly slice red onion. If using lettuce, shred or rinse and dry cabbage/lettuce so it is crisp.

Toast the buns

Butter the insides of the sub rolls and toast in a skillet or under a broiler until lightly golden, about 1–2 minutes per side. This prevents sogginess and adds flavor.

Assemble sandwiches

Spread about 2 tbsp of the sandwich sauce on the bottom half of each toasted roll. Place shredded lettuce (about 1/2 cup per sandwich) on top of the sauce, then a fried fish fillet. Top fish with 1–2 tomato slices, a few red onion slices, and 4 pickle slices. Spoon an additional 1 tbsp sauce on the top bun if desired, then close the sandwich. Serve immediately with lemon wedges for squeezing over the fish.