Classic English Fish and Chips with Mushy Peas and Tartar Sauce

Prepare the fries: Rinse the cut potatoes in cold water until the water runs clear, then pat them completely dry. Fry the potatoes in batches in vegetable oil heated to 325°F (160°C) for 5-7 minutes, until softened but not browned. Remove and drain on paper towels. Increase oil temperature to 375°F (190°C).

While potatoes are pre-frying, prepare the fish batter: In a large bowl, whisk together 1 1/2 cups all-purpose flour, baking powder, 1/2 teaspoon salt, and 1/4 teaspoon black pepper. Gradually whisk in the cold lager beer until a smooth batter forms. Season the cod fillets with the remaining 1/2 teaspoon salt and 1/4 teaspoon black pepper, then dredge them in the remaining 1/2 cup dry flour.

Fry the fish: Dip each floured cod fillet into the beer batter, ensuring it's fully coated. Carefully lower the battered fish into the 375°F (190°C) oil. Fry 1-2 fillets at a time for 6-8 minutes, turning once, until golden brown and cooked through. The internal temperature of the fish should reach 145°F (63°C). Remove and drain on paper towels.

Finish the fries: Return the pre-fried potatoes to the 375°F (190°C) oil and fry for another 3-5 minutes, or until golden brown and crispy. Remove and season immediately with salt.

Prepare the mushy peas: Heat the canned mushy peas in a small saucepan over medium heat for 3-5 minutes, stirring occasionally, until warmed through. If using dried marrowfat peas, cook according to package directions until tender and mushy.

Make the tartar sauce: In a small bowl, combine mayonnaise, chopped dill pickles, chopped fresh parsley, and lemon juice. Stir well to combine.

Serve immediately: Arrange the crispy fish, golden fries, warm mushy peas, and a generous dollop of tartar sauce on plates. Garnish with lemon wedges if desired.