01 -
In a bowl, combine the chopped parsley, tarragon, minced shallot, and minced cornichons. Remove the yolk from the hard-boiled egg and crumble it; dice the white. Add both yolk and white to the bowl. Add the vinegar, pinch of salt, Dijon mustard, mayonnaise, and hot sauce. Stir until thoroughly combined and set aside.
02 -
In a large mixing bowl, whisk together cake flour and baking soda. Gradually pour in beer, stirring continuously. The batter should be thin, able to coat the back of a fork lightly. A few lumps are acceptable. Set aside.
03 -
Pour vegetable oil into a deep heavy-bottomed pan, filling no more than 5 cm below the rim. Heat oil to 175°C.
04 -
Season halibut fillets on both sides with salt. Test oil readiness by dropping in a few drops of batter; when they float to the surface and sizzle, it's hot enough. Remove any crisp tester pieces with a slotted spoon. Working with one fillet at a time, dip the halibut into the beer batter, letting excess drip off. Lower halfway into the hot oil, allowing a crust to form for 10 seconds before gently releasing. Fry up to three fillets at a time, avoiding overcrowding. Cook each piece for 3–4 minutes until golden and crisp.
05 -
When cooked, transfer the fish to a baking sheet lined with a wire rack to drain excess oil. Season immediately with flaky sea salt. Serve with prepared tartar sauce and lemon wedges.