First Step: Prep your ingredients Slice the onion into 1/2-inch thick rings and separate carefully. Pat cod fillets dry with paper towels to help the batter stick better and keep the coating crisp.

Second Step: Make the batter In a large bowl, whisk together the all-purpose flour, optional cornstarch for extra crispiness, baking powder, salt, black pepper, paprika, and garlic powder. Add the egg and slowly whisk in the cold ale (or cold beer/club soda) until the batter is smooth. Let it rest briefly for light texture.

Third Step: Prepare onion rings Dredge onion rings in flour, dip them into buttermilk, then coat again with the seasoned flour mixture. Press into panko breadcrumbs if extra crunch is desired. Set aside.

Fourth Step: Heat the oil Preheat vegetable oil in a deep pot or fryer to 350-375°F (175-190°C), using a thermometer for accuracy.

Fifth Step: Fry onion rings Fry onion rings in batches without overcrowding. Cook for approximately 2-3 minutes until golden and crisp. For extra crispiness, double-fry by first frying for 1 minute, draining, then frying again for 2 minutes. Drain on wire racks or paper towels and lightly salt.

Sixth Step: Fry lemon slices and parsley (optional garnish) Quickly fry thin lemon slices and parsley sprigs in hot oil for about 1 minute until crisp. Drain and set aside.

Seventh Step: Fry the cod Lightly dust the cod pieces with flour, then dip in batter, allowing excess to drip off. Fry for 4-7 minutes per side, turning gently and pressing lightly to ensure even contact with oil. Fry until golden brown and cooked through. Drain on a wire rack and sprinkle with salt.

Final Step: Arrange and serve Place the crispy battered cod and onion rings on a large platter. Garnish with fried lemon slices, fresh parsley, and lemon wedges. Serve with tartar sauce, ketchup, spicy mayo, or malt vinegar as preferred. Enjoy immediately for the best texture.