In a bowl, high-tail the mayonnaise with the ketchup, lemon juice and Tabasco.
Pour the water into a shiny bowl. Utilizing a handheld electric mixer at low escape, beat in the 2 cups of flour, 1/2 teaspoon of salt and the baking soda. Drive the batter into one other bowl.
In a shiny saucepan, heat the oil to 360°. Line a rack with paper towels. Dirt 5 pieces of cod with flour, then tap off the extra. Dip the cod in the batter, scraping the pieces lightly against the facet of the bowl to secure away extra batter, and add to the hot oil. Fry over moderate heat unless golden and crisp, about 7 minutes. Utilizing a slotted spoon, switch the fish to the rack. Repeat with the last fish and batter. Sprinkle with salt and back without prolong with the sauce.
A knowing, crisp, citrusy Sancerre.