Preheat the oven to 180°C/350°F/gas 4.

Peel and slice the potatoes into chips.

Add a squeeze of lemon juice and season to taste with sea salt and black pepper – you can either mush the peas up in a food processor, or mash them by hand until stodgy, thick and perfect for dipping your fish into. Keep them warm until needed.

Pour the sunflower oil into a deep fat fryer or a large sturdy pan and heat it to 190°C/375°F.

Mix ½ a teaspoon of salt and 1 teaspoon of pepper together, then use it to season the fish fillets on both sides – this will help to remove any excess water, making the fish really meaty.

Whisk the flour, beer and baking powder together until nice and shiny – the texture should be like semi-whipped double cream (i.e. it should stick to whatever you're coating).

Dust each fish fillet in a little of the extra flour, then dip into the batter and allow any excess to drip off. Holding one end, gently lower the fish into the oil one by one, working carefully so you don't get splashed – it will depend on the size of your fryer or pan how many fish you can cook at once.

Cook for 4 minutes, or until the fish is cooked through and the batter is golden and crisp, then remove to kitchen paper to drain.

Meanwhile, parboil the chips in boiling salted water for 4 to 5 minutes, or until softened but still retaining their shape, then drain and steam dry.

While the chips are frying, transfer the fish from the kitchen paper to a baking tray. Place in the oven for a few minutes to finish cooking – this way they will stay crisp while you finish off the chips.

When the chips are done, drain them on kitchen paper, season with salt, and serve with the fish and mushy peas. Other things to have on the table are some crunchy sweet pickled gherkins, some pickled onions (if your other half isn't around!) – and pickled chillies are good, too. Then you want to douse it all with some cheap malt vinegar and nothing other than Heinz tomato ketchup.