I prefer the coating on my fish to be very light and crisp, in the style of tempura, and some of the better chipper vans (can there be a "better" chipper van?) and pubs of the UK. I also like my potatoes fried properly -- something that's impossible in a van, difficult in a restaurant, and rather easy at home.
Fish and Chips
Fryer or pan set up as fryer
Brown paper bags
Enough potato by weight for 2, cut into chips, soaked in water
Enough oil for frying
2 cups flour
1 tbs double acting baking powder
1 tsp salt
1 ex-large egg
1-1/2 cups, ice-cold club-soda or seltzer, or bottle of lager beer, divided in halves
1 or 2 ice cubes
1 pound cod, haddock or plaice fillets, cut into long triangular wedges
1/2 cup rice flour, or corn starch
A proper chip is no small thing. Peel your potatoes, and cut them into chips about the size of your index or driver's finger. Cover the potatoes with water, discard the water, and cover again with fresh water. Potatoes should soak at least 45 minutes, and up to 4 hours.
While the potatoes are soaking, begin the batter. Sift the flour baking powder and salt together. Beat the egg and add it and about 3/4 cup liquid and stir to combine a very smooth batter. Cover with cling wrap, and hold in the refrigerator. The partially completed batter should be held for at least 45 minutes and up to 2 hours.
When ready to cook, Wash and dry your fillets, then portion into long triangular wedges, each about 4 oz. English style is skin on; American is skin off. Dust the fillets with enough rice powder or corn starch, so they are fully covered, and completely dry. Shake off any excess and reserve the fish on a rack.
Heat the oil to 325. Drain enough chips to fill the fryer without crowding, reserving three for later. (You may have to work in batches.) Dry them thoroughly with a towel. Cook the potatoes through, about 5-6 minutes. They will either not brown at all, or only brown slightly.
Set the potatoes aside to drain on paper. A brown paper bag works better than paper towels for draining oil.
Raise the oil temperature to 375.
Remove the batter from the refrigerator. Add the ice cube and the remaining liquid, and stir until just combined. Dip the fish in batter until coated.
If you only have one smallish fryer cook as follows: Fry the fish until done, about 5 minutes. While the fish is frying drain, dry and reserve the remaining three chips. As soon as the fish comes out of the oil, add those chips, and let them cook for 60 seconds only. Then remove and discard. (Their purpose is to clean any fish taste that got into the oil.) Immediately, return the partially cooked chips to the oil, and cook until they pick up some color, about 5 minutes. Remember, they are already cooked
If your fryer is big enough to handle the temperature shock, you may fry the fish and partially fried chips at the same time. If you do so, chips on the bottom, fish on top.
If you have two fryers, fry the fish and the partially fried chips simultaneously.
Drain the fish and the chips on fresh brown paper. Salt lightly while still hot.
Plate the fish and chips with lemon wedges. Serve with malt vinegar
on the side.
Hope this helps,