2) Fry potatoes until golden brown, roughly 10 minutes removing with a slotted spoon or spider. Hold in low oven to keep warm while cooking the fish.
Beer battered fish:
1) Preheat oven to 110C/Gas 1/4.
2) Pour in the bottle of beer into a large bowl. Sift three-quarters of the flour into the bowl, whisking in gently until just combined. Whisk in house seasoning. Pat fish dry and season on both sides with salt and pepper.
3) Coat the fish in the beer batter. Dredge the pieces of fish in remaining flour and slide into oil as coated. Fry fish, turning over frequently, until deep golden and cooked through, 4-5 minutes. Transfer to a paper towel-lined baking sheet and keep warm in oven.
4) Fry remaining fish in batches, returning oil to 190C between batches. Serve fish with chips.
Combine ingredients and store in an airtight container for up to 6 months.