Peanut butter cookies are a cookie dating back to the early 1930s.George Washington Carver (1864-1943), an African-American agricultural extension educator, from Alabama's Tuskegee Institute, was the most well known promoter of the peanut as a replacement for the cotton crop, which had been heavily damaged by the boll weevil. He compiled 105 peanut recipes from various cookbooks, agricultural bulletins and other sources. In his 1916 Research Bulletin called How to Grow the Peanut and 105 Ways of Preparing it for Human Consumption, he included three recipes for peanut cookies calling for crushed/chopped peanuts as an ingredient. It was not until the early 1930s that peanut butter was listed as an ingredient in the cookies. Why are peanut butter cookies traditionally marked with a criss cross pattern?The Peanut Butter Balls recipe in the 1931 edition of Pillsbury's Balanced Recipes contains the first known written instance of instructing the cook to press the cookies using fork tines. The recipe does not explain why this advice is given, though peanut butter cookie dough is dense, and without being pressed, it will not cook evenly. Using fork tines to press the dough is a convenience; bakers can also use a cookie press.