Salty Thin and Crispy Oatmeal Cookies

From America's Test Kitchen Season 10: All-Time Cookie Favorites

Thin and crispy oatmeal cookies can be irresistible—crunchy and delicate, these cookies really let the flavor of the oats take center stage. But the usual ingredients that give thick, chewy oatmeal cookies great texture—generous amounts of sugar and butter, a high ratio of oats to flour, a modest amount of leavener, eggs, raisins, and nuts—won’t all fit in a thin, crispy cookie. We wanted to adjust the standard ingredients to create a crispy, delicate cookie in which the simple flavor of buttery oats really stands out.

Given this cookie’s simplicity, creating a rich butter flavor was critical, so we kept almost the same amount of butter as in our standard big, chewy oatmeal cookie, but we scaled back the amount of sugar. Fine-tuning the amount and type of leavener led to a surprising result that solved our texture and shape problems. During baking, large carbon dioxide bubbles created by the baking soda and baking powder (upped from our traditional recipe) caused the cookies to puff up, collapse, and spread out, producing the thin, flat cookies we were looking for. Baking the cookies all the way through until they were fully set and evenly browned from center to edge made them crisp throughout but not tough.