Shrimp Haddock Po Boy Recipe

Combine mayonnaise, Creole or Dijon mustard, hot sauce, prepared horseradish, lemon juice, Worcestershire sauce, paprika, cayenne, chopped capers, minced shallot, minced parsley, salt, and pepper in a small bowl. Whisk until smooth and taste to adjust seasoning. Cover and refrigerate at least 20 minutes while preparing the rest so flavors marry.

Trim and Soak

Rinse and pat dry the haddock strips and shrimp with paper towels. Place them in a bowl and pour buttermilk over the seafood. Lightly beat the egg and add to the bowl, stirring to combine. Let the seafood soak for 10–15 minutes; this helps tenderize and helps the coating adhere.

Make Dredge and Breading Stations

In a shallow bowl or plate, whisk together 1 cup flour, cornstarch, cornmeal, 1 tsp salt, 1 tsp black pepper, 1 tsp cayenne, and 1 tsp garlic powder. In a second shallow bowl, beat the remaining egg (if using a second egg; note recipe used 1 egg in soak — if you prefer a separate wash, beat an additional egg) or reserve the buttermilk mixture as the wet wash. Place panko in a third shallow bowl. Set up as: flour dredge, wet (buttermilk/egg) wash, panko.

Dredge and Bread

Working in batches, remove a piece of seafood from the buttermilk, let excess drip off, dredge lightly in the flour mixture, dip back briefly in the wet (buttermilk) mixture, then press into panko so the surface is evenly coated. Place breaded pieces on a tray and let rest 5 minutes so coating sets. Repeat for all shrimp and haddock strips.

Heat Oil

Pour vegetable oil into a heavy skillet or Dutch oven to a depth of about 1 to 1.5 inches (about 3–4 cups depending on pan). Heat over medium-high until oil reaches 350°F (175°C). If you don't have a thermometer, test by dropping a small piece of breading — it should sizzle and float, browning in ~45–60 seconds.

Fry Seafood

Fry breaded seafood in batches without crowding the pan. Fry shrimp 1.5–2.5 minutes until golden and cooked through; fry haddock strips 2.5–3.5 minutes, flipping if needed, until crisp and opaque inside. Maintain oil temperature between 325–350°F; adjust heat as needed. Remove with a slotted spoon or spider and drain on a rack set over a baking sheet or paper towels. Season immediately with a light sprinkle of salt.

Toast Rolls

Slice the hoagie rolls lengthwise without cutting fully through. Spread softened butter on the cut sides. Place rolls in a skillet or under a broiler for 1–2 minutes until lightly toasted and golden — watch closely to avoid burning.

Build Sandwiches

Spread a generous layer (about 2–3 tbs) of remoulade sauce on both cut sides of each toasted roll. On the bottom half, layer shredded lettuce (about 1 cup per sandwich), then arrange the fried haddock strips and shrimp (half the seafood per sandwich so each gets roughly 6 shrimp + 6 oz haddock). Add tomato slices and pickle slices. Spoon a little extra remoulade on top if desired and garnish with sliced green onion. Close the sandwich and press gently.

Serve

Cut each po' boy in half if desired and serve immediately while filling is hot and bread is crisp. Provide extra remoulade and hot sauce on the side.