Crisp Fish with Thick Chips and Peas

Ingredients

• 4 boneless white-fish fillets, 150 g raw edible weight each
• 900 g floury potatoes, cut into 1.5 cm-thick chips
• 30 g neutral oil for the chips
• 1.5 litres neutral oil for deep-frying, not all absorbed
• 160 g plain flour, divided
• 50 g cornstarch
• 1 tsp baking powder
• 240 ml chilled sparkling water
• 300 g frozen peas
• 15 g unsalted butter
• 8 g fine salt, divided
• 1/2 tsp ground black pepper

Let’s make it

1. Heat the oven to 425°F / 220°C with a large baking tray inside. Boil the potato chips in water for 5 minutes, drain carefully and let steam-dry for 3 minutes.
2. Toss the chips with 30 g oil and 3 g salt. Spread on the hot tray and roast for 40–45 minutes, turning halfway through, until golden and crisp.
3. When the chips have 15 minutes remaining, heat the frying oil in a deep heavy saucepan or fryer to 350°F / 175°C. Use enough for a 5 cm depth while keeping the vessel less than half full. Keep a lid nearby and never add water to hot oil.
4. Pat the fish dry and season with 2 g salt and the pepper. Put 30 g flour on a plate. Whisk the remaining 130 g flour, cornstarch, baking powder, 2 g salt and cold sparkling water briefly into a batter. Dust each fillet with flour, then dip in batter.
5. Carefully lower two fillets at a time into the oil, away from you. Fry for 5–7 minutes until golden and the fish reaches 145°F / 63°C at the thickest point. Drain on a rack and repeat, letting the oil return to temperature. Discard batter and flour exposed to raw fish.
6. Boil the peas in water for 3–4 minutes, drain and toss with the butter and remaining 1 g salt. Divide the fish, chips and peas among four plates and serve immediately.