The chocolate chip cookie was created in 1938 at the Toll House Inn in Whitman, Massachusetts, by Ruth Graves Wakefield. The popular legend — that she was out of baker's chocolate and improvised by chopping a Nestlé semi-sweet bar into her dough expecting it to melt — was mostly marketing. Wakefield was a trained dietitian and restaurant owner; she almost certainly designed the cookie on purpose, and called her first version the “Chocolate Crunch Cookie.”

Nestlé acquired the rights in 1939 in exchange for a lifetime supply of chocolate and printed the recipe on the back of every semi-sweet bar. In 1941 they switched to purpose-made chocolate chips. Soldiers shipped Toll House cookies overseas during WWII and the recipe went global. The Toll House Inn itself burned down in 1984, but the name has outlived the building by decades.

The modern era has branched in every direction. Mrs. Fields (1977) and Famous Amos (1975) took the cookie retail. Levain Bakery (1994) pushed it to a six-ounce half-baked dome. David Leite's 2008 New York Times piece on Jacques Torres popularized the 36-hour cold ferment and larger, sea-salted format that dominates bakeries today. Tahini, miso, brown butter, sourdough discard, malted milk powder, reverse-creaming, “edge piece” pan cookies — all are variations on a form Wakefield would still recognize. Each variant is a different position on the same set of knobs.