Well ahead of time, peel the potatoes and cut them into chips, the chunkier the better.
Preheat the oil for deep-frying to 135°C.
Cook the chips for 10 minutes and drain on kitchen paper. (These can be cooked ahead of time or in batches, set aside and then finish after the fish is ready.)
To make the batter, whisk together the flour and cornflour. Quickly whisk in the Guinness and the sparkling water, taking care not to over-mix (it doesn’t matter if the mixture still has some lumps in it)
Place the seasoned flour into a freezer bag and carefully put the fish fillets in it, moving them around until both have a light, even coating of flour.
Preheat the oven to gas 3, 160°C, fan 150°C and heat the fat for deep-frying again, this time to 180°C, ready for the fish.
Dip the floured fish into the Guinness batter. Get a good coating and deep-fry for 5-6 minutes. Drain on kitchen paper and keep warm in the oven. Finish the chips by deep-frying them again at 180°C, which will crisp them up and warm them through.
Serve peas and ice-cold beer!
Soaking the uncooked chips in cold water gets rid of excess starch and using salted water adds a bit of extra taste, as the potatoes absorb the salt. You must remember to dry off excess water in a tea towel before putting them in the hot fat!
Cooking the chips in two stages gives really light, fluffy chips with a superb crispy outer.
*Inspired by Robert C. featured in the Realfood Cookbook
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