Imagine a chocolate chip cookie. Better yet, get one. Take a bite. Savor the flavor and texture. What makes a chocolate chip cookie so delicious? Save for the chocolate chips, most of the ingredients aren’t that appealing on their own. Few people reach for a big spoonful of flour to satisfy a craving. Other ingredients are not obvious except to bakers: salt, vanilla, baking soda. Yet each is essential to the final product.