For Flat Cookies- Flat=Fat. The more fat (real butter) in your cookie, the more it will spread. If you want a flatter cookie, use butter instead of margarine or shortening. Replace some of the brown sugar with granulated sugar. Also, bring your dough to room temperature before baking. Try White Chocolate Macadamia Nut or M&M.
For Puffy Cookies- You know when the brownie mix package says for cake-like brownies, add an extra egg? The same applies for cookies. Or, you can use margarine in place of butter. Reducing the amount of white sugar in the recipe works, too. Try Banana Walnut Chocolate Chip or Apple Pie or Sour Cream Cookies.
For Chewy Cookies- Use brown sugar or honey in place of white sugar. Let the cookies cool on the pan for a few minutes before transferring to a cooling rack to cool completely. Try Coconut Oatmeal or Peanut Butter Pretzel Cookies.
For Crispy Cookies- Use butter instead of margarine for crispy cookies. For recipes that call for two eggs, instead use one whole egg and one egg yolk. Immediately transfer cookies to a cooling rack after removing them from the oven. Try Oatmeal Butterscotch or Lime Sugar Cookies.
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