Triple-Cooked Chips

Where the method comes from

Steak and chips is a dish that good restaurants are judged on as much by the side as by the meat. British chef Heston Blumenthal, whose restaurant The Fat Duck holds three Michelin stars, spent several years in the 1990s experimenting with chips and arrived at the triple-cooking method. Today his triple cooked chips are the standard in many gastropubs and steakhouses, and the technique is described in his books and television programmes.

The physics of crunch

A crisp shell is a dehydrated layer of gelatinised starch. A single fry handles this poorly: the outside browns before it dries, and within five minutes the crust goes soft. The method breaks the process into three steps, each with its own purpose.

1. Boil until cracked. The batons are simmered in salted water until almost falling apart. Starch on the surface swells and micro-cracks appear along the edges. During frying, oil lingers in these cracks and forms the crisp, glassy structure.

2. Dry with cold. The boiled potatoes are laid on a rack and refrigerated uncovered for at least an hour. Cold, dry air pulls moisture from the surface — the drier the chip, the less the oil spits and the better the crunch.

3. Two fries. The first, at 130 °C, is not browning but a confit: water evaporates from the surface layer and a thin skin forms, still without colour. The potatoes are chilled again. The second fry, at 180 °C, takes a few minutes and brings golden colour and crunch.

Which potato to choose

You need floury, high-starch varieties (in the UK Maris Piper, in the US Russet; any floury, yellow-fleshed potato will do). Waxy new potatoes do not work: they contain little starch and more sugar, so they darken quickly and stay dense.

About oil and calories

You will need 1.5–2 litres of refined oil with a high smoke point. In a deep fryer oil is absorbed only by the surface: well-dried chips take up about 6% of their own weight after two fries. That is why the ingredients list 60 g of oil — what ends up in the portion, not the whole volume of the fryer. After frying, strain the oil and reuse it 2–3 times.

Safety

Fry in a deep pan no more than a third full of oil, with a thermometer. Add the potatoes in small batches and only when dry. Never put out burning oil with water — cover with a lid and turn off the heat.

Serving

Salt immediately after frying, while the surface glistens with oil, so the salt sticks. Fine sea salt or thyme salt, aioli or mayonnaise with Dijon mustard are the classic companions.