Triple-cooked chips are a type of chips developed by the English chef Heston Blumenthal. Blumenthal began work on the recipe in 1993, and eventually developed the three-stage cooking process. The chips are first simmered, then cooled and drained using a sous-vide technique or by freezing; deep fried at 130 °C (266 °F) and cooled again; and finally deep-fried again at 180 °C (356 °F). The result is what Blumenthal calls "chips with a glass-like crust and a soft, fluffy centre".