dissolves in the limited amount of moisture When the dough heats up during baking, more sugar can dissolve, and the added liquid causes the cookie to soften and spread Then when the cookie cools, some of the sugar recrystallizes, and the initially soft cookie develops a distinctive snap — a process that may take a day or two Other forms of sugar — honey, molasses, corn syrup — tend to absorb water rather than crystallize (chapter 12), so when heated they form a syrup that permeates the cookie, helps it to spread, and firms as it cools, making it moist and chewy Eggs Eggs generally provide most of the water in a cookie mix, as well as proteins that help bind the flour particles together and coagulate during baking to add solidity The fat and emulsifiers in the yolk enrich and moisten The higher the proportion of whole eggs or yolks in a recipe, the more cake-like the texture Fat Fat provides richness, moistness, and suppleness When it melts during cooking, it lubricates the solid particles of flour and sugar and encourages the cookie to spread and thin — a quality that is sometimes desirable, sometimes not Because butter melts at a lower temperature than margarine or shortening, it gives cookies more time to spread before the protein and starch set Butter is about 15% water, and is the main or only source of moisture in such low-egg recipes as shortbread and tea cookies Leavening Leavening, whether tiny bubbles of air or of carbon dioxide, helps tenderize cookies, and encourages them to puff Many cookies are leavened only with air bubbles incorporated when the sugar is creamed with the fat, or beaten with the eggs Some are supplemented with chemical leavenings Alkaline baking soda may be used when the dough includes such acid ingredients as ... spread before the protein and starch set Butter is about 15% water, and is the main or only source of moisture in such low-egg recipes as shortbread and tea cookies Leavening Leavening, whether tiny... bubbles of air or of carbon dioxide, helps tenderize cookies, and encourages them to puff Many cookies are leavened only with air bubbles incorporated when the sugar is creamed with the fat,... provides richness, moistness, and suppleness When it melts during cooking, it lubricates the solid particles of flour and sugar and encourages the cookie to spread and thin — a quality that is