Chocolate chip cookie

The chocolate chip cookie is an American drop cookie of butter, brown and white sugar, egg, flour, a little baking soda and salt, with pieces of semi-sweet chocolate folded through a dough that is scooped straight onto the tray rather than rolled or cut. It dates to the 1930s and to Ruth Wakefield's Toll House Inn in Whitman, Massachusetts; her recipe was printed on the back of Nestlé's chocolate bar wrappers and later on the bags of the purpose-made chips the company introduced in 1939, and that printed recipe is still the baseline most American home bakers start from. It has since split into recognisable schools: the thin, crisp, bakery-case cookie; the thick, soft, under-baked style of the mall chains; the large, craggy, brown-butter and sea-salt cookie of the 2010s New York bakery; and the chilled-dough, oversized version sold by weight. All are the same dish, and all are judged on the same three things: edge, centre and chocolate.