Peel (optional) and cut potatoes into 1/2-inch to 3/4-inch thick sticks. Place cut potatoes in a large bowl of cold water and soak 30 minutes to 1 hour to remove excess starch. Drain and rinse, then pat completely dry with clean kitchen towels or paper towels.

First Fry (Blanch)

Heat oil in a heavy pot or deep fryer to 325°F (160°C). Fry potatoes in batches (do not overcrowd) for 4–6 minutes until soft but not browned. Remove with a slotted spoon and drain on a wire rack or paper towels. Let rest while you prepare batter and fish.

Second Fry (Crisp)

Increase oil temperature to 375°F (190°C). Return blanched fries to the hot oil in batches and fry 2–4 minutes until golden brown and crisp. Drain on paper towels, immediately season with 1 tsp salt (or to taste), and keep warm in a low oven (200°F/95°C) if needed.

Fish & Batter

Prep Fish

Pat fish fillets dry with paper towels. Cut into serving-size pieces (about 4–6 oz each). Season lightly with a pinch of salt and pepper. Set up a dredging station with the 1/2 cup flour in a shallow dish for dusting.

Make Batter

In a bowl, whisk together 1 cup all-purpose flour, 1/4 cup cornstarch, 1 tsp baking powder, 1 tsp salt, and 1/2 tsp black pepper. If using the egg, whisk the egg lightly in a separate small bowl and add to the dry mix. Gradually pour in 1 cup very cold beer while whisking until you have a smooth batter with the consistency of thick pancake batter — it should coat the back of a spoon. Do not overmix; some small bubbles are desirable. Keep batter cold (place bowl in a larger bowl with ice if your kitchen is warm).

Heat Oil

Heat vegetable oil in a deep pot or fryer to 350–360°F (175–180°C) for frying the battered fish. Use a thermometer to maintain consistent temperature; oil that is too cool will produce greasy batter, too hot will burn the exterior before the fish cooks.

Dredge & Batter Fish

Lightly dredge each seasoned fish piece in the 1/2 cup flour, shaking off excess. Holding the fish by one end, dip into the cold beer batter to fully coat, allowing excess to drip off for 5–10 seconds.

Fry Fish

Carefully lower battered fish into the hot oil in batches, taking care not to overcrowd (2–3 pieces at a time depending on pot size). Fry for 4–6 minutes, turning once if needed, until batter is golden brown and an instant-read thermometer reads 135–145°F (57–63°C) for the thickest part of the fish (or flaky and opaque). Remove with a slotted spoon and drain on a wire rack or paper towels. Keep warm in a low oven if serving in batches.

Tartar Sauce & Finishing

Make Tartar Sauce

In a small bowl, combine 1/2 cup mayonnaise, 2 tbsp finely chopped dill pickle, 1 tsp chopped capers (if using), 1 tbsp fresh lemon juice, 1 tbsp chopped parsley, 1/4 tsp salt, and 1/4 tsp black pepper. Mix until well combined and taste — adjust salt, lemon, or chopped pickles to preference. Refrigerate until ready to serve.

Serve

Arrange hot fries and beer-battered fish on plates or a platter. Serve immediately with tartar sauce, lemon wedges, and malt vinegar or ketchup if desired. Enjoy while hot and crisp.