When making cookies, most of us just use recipes from cookbooks. While this usually produces the desired results (or close – remember a recipe is just a starting point), it takes all the fun out of really understanding why the cookies turn out the way they do – crumbly, chewy, crunchy, etc.Today I am going to explore what makes cookies tick and delve into some cookie theory. You may use the information to play around with your recipes and get your cookies just the way you like them.Cookies have various textures that determine the type of cookie.The characteristic softness of soft cookies is achieved by a combination of factors.The higher the liquid content, the softer the cookie. Elevated moisture level slows drying out. Fat is a tenderizer, so the more butter, margarine and oil in the cookie, the softer it will be. Sugar also softens cookies due to its hygroscopic nature – it attracts moisture.The same applies to honey, molasses, corn syrup, etc. The larger the mass of the cookie, the softer the interior will be, especially when baked at a higher temperature for a shorter time. You may prolong the softness of cookies by coating them with chocolate, for example, to prevent them from drying out.If you want a crispy cookie, you basically do the opposite of what is required for a soft cookie. The less sugar used, the crispier the cookie, since less moisture is retained. Smaller, thinner cookies dry out more quickly and are crispier than larger mass cookies. Baking at a lower temperature for a longer time dries the cookie out. Take biscotti, for example. They are double baked to dry them out even further. To keep cookies crisp, coat them or store them in an airtight container, where they cannot absorb moisture.For those who like a chewy cookie, read on. Firstly, you need a higher sugar content to make the cookie softer. Use high protein flour, such as bread flour instead of cake flour, which will result in cookies with a higher gluten content and increased chewiness.Increased mixing time increases the gluten further. Adding extra protein ingredients such as whole eggs or egg whites will also make the cookie more chewy, as they gelatinize when baked.Do you love shortbread? Cookies that have a sandy texture are made with dry dough with more fat content, less sugar and less liquid. Egg yolk is the main liquid, to ensure the least amount of gluten formation. The higher fat content coats the flour particles, not allowing absorption of moisture. It is therefore important not to over-mix the fat-flour stage; otherwise, the flour will be completely mixed into the fat, tenderizing it and making it soft.Do your cookies spread when baking, sometimes too thin, or do not spread at all? There are scientific formulas for determining how a cookie spreads. Industrial cookie manufacturers have to get each cookie the exact same size; otherwise, it will not fit into the packaging. For us home bakers, it is sufficient to rely on a few rules of thumb.The first factor determining cookie spread is the size of the sugar granules. Granulated sugar spreads less than icing sugar. The more you cream the sugar with butter/margarine, the more the cookie will spread because additional air is incorporated, which expands when baked. The same applies to baking powder: The more rising agents, the more air and the more spread. Cookies baked at lower temperatures tend to spread more. Lower protein flour cookies, such as cake flour, will spread more than high protein flour or bread flour. If you do not cream the sugar and butter correctly, scraping remnants off the sides of the bowl, some ingredients may not be mixed thoroughly in the dough, causing run-out – butter/sugar flowing out of the cookie and forming a very thin, hard film around the cookie base. If your cookies are spreading too much or too little, play around with these parameters.About baking the cookies. Each type of cookie has specific instructions for baking to determine the required texture. Some need a short, hot bake, while others need a longer, cooler bake (see above). The general rule of thumb is to bake cookies at 175° for convection ovens or 190° for non-convection, home ovens.How do you know when the cookie is done? Mostly cookies come out of the oven very soft and fragile and need to cool down to set. So firmness is not a measure of “doneness.” Rather, try to lift the edge of one of the cookies while it is in the oven. If it easily detaches from the baking paper, it is probably done. If it sticks, wait a little longer.Finally, a classic cookie recipe. These oatmeal cookies are earthy with an irresistible aroma, extremely healthy and are best chased with a glass of milk! OATMEAL RAISIN COOKIES✔ 120 gr. butter or margarine✔ 1¼ cups brown sugar ✔ 1 egg ✔ 1½ tsp. vanilla essence ✔ 1¼ cups bread flour ✔ 1½ tsp. baking powder ✔ ½ tsp. baking soda ✔ ½ tsp. salt✔ 150 gr. rolled oats✔ 130 gr. raisinsCream butter and sugar until mixed but not fluffy. Add eggs and vanilla gradually. Combine dry ingredients separately and add these to mixing bowl until about 50% mixed. Add oats and raisins until incorporated. Roll dough into a log, the diameter of which is the desired size of the cookie. Cut cookies to the desired thickness and place on a baking sheet lined with parchment paper. Bake at 175° for 12 to 15 minutes in a convection oven. Master baker Les Saidel is CEO of the Saidel Artisan Baking Institute (www.saidels.com), which specializes in training and education in the field of organic, healthy, artisan baking, and is the inventor of Rambam Bread. He also lectures and works as a consultant in the fields of cereal chemistry, health and nutrition.