Ruth Wakefield, a chef, ran out of baker's chocolate and decided to use chopped-up semi-sweet chocolate instead. The chocolate didn't melt completely, creating the first chocolate chip cookies.
Legend has it that in 1853, a chef named George Crum sliced potatoes too thin and fried them too long to spite a customer who complained about the thickness of his fried potatoes. Instead, the thin, crispy potato chips were a hit.
In 1905, 11-year-old Frank Epperson accidentally left a glass of soda powder and water with a stirring stick on his porch overnight during freezing temperatures. The mixture froze, and the popsicle was born.
The Kellogg brothers left a pot of boiled wheat to sit, and when they returned, it was stale. They rolled it out anyway and found that it formed flakes. They then tried the same process with corn, leading to the creation of corn flakes.
At the 1904 St. Louis World's Fair, an ice cream vendor ran out of dishes and teamed up with a nearby waffle vendor who rolled his waffles into cones, leading to the creation of the ice cream cone.
Edward Wilson was experimenting with a machine to make animal feed when he accidentally discovered a technique for making puffed corn snacks, which later became cheese puffs.
A monk named Dom Pérignon accidentally discovered champagne when he bottled wine before it finished fermenting. The trapped carbon dioxide created the bubbles characteristic of champagne.
According to Chinese legend, tofu was discovered by accident over 2,000 years ago when a Chinese cook accidentally curdled soy milk with a bit of nigari seaweed.