A peanut butter cookie is a type of cookie that is distinguished for having peanut butter as a principal ingredient. The cookie originated in the United States, its development dating back to the 1910s.

Early peanut butter cookies were either rolled thin and cut into shapes, or else they were dropped and made into balls; they did not have fork marks. The first reference to the famous criss-cross marks created with fork tines was published in the Schenectady Gazette on July 1, 1932. The Peanut Butter Cookies recipe said: “[s]hape into balls and after placing them on the cookie sheet, press each one down with a fork, first one way and then the other, so they look like squares on waffles.”

Pillsbury, one of the large flour producers, popularized the use of a fork in the 1930s. The Peanut Butter Balls recipe in the 1933 edition of Pillsbury’s Balanced Recipes instructed the cook to press the cookies using fork tines. These early recipes do not explain why the advice is given to use a fork, though. The reason is that peanut butter cookie dough is dense, and unpressed, each cookie will not cook evenly.

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