For the pan-fried fish, heat the oil over a medium heat in a frying pan and add a little butter.
Dust the fish with flour and pan fry skin side up for 3-4 minutes each side, then allow to rest.
If you prefer fish in batter:
Heat the oil to 185°C
Place the flour into a bowl, add enough lager or water to form a smooth batter, not too thick
Flour the fillets carefully then place into the batter one at a time, coat well and place straight into the hot oil. Cook no more than 4 at a time or the heat in the oil will drop too much.
Cook for 7-8 minutes stirring occasionally until golden
For the chips:
Peel and wash the potatoes well, then cut into fingers say 1.5cm wide.
Re wash and dry well in kitchen paper or towel.
Heat the oil to 190C leave for 10 minutes then reduce to 175C. Never fill a fryer more than two thirds full.
Plunge small amounts of chips into the oil and cook for 3-4 minutes to soften, but with no colour. Shake off the excess oil and cool on a tray, not piled up. Repeat until all are done. You can chill at this point.
When ready to serve turn up the oil to 185-90C.
Cook in small batches until crisp and golden, drain well and season well with salt and vinegar if you like.