Julia M. Usher posted:Could be a few things:
(1) Type of flour used (Cake or pastry flour - i.e., lower protein flour - will create a more delicate result than all-purpose flour. The former are usually in the 7-9% protein range; the latter in the 10-12% range, and this can make a big difference. Protein percentages can usually be found/calculated from the nutritional info on the packaging if you are not sure.)
(2) Quantity of flour used (All else being the same, the more flour in the recipe relative to other ingredients, the more sturdy the dough will be.)
(3) Thickness to which you rolled the dough (Obviously, the thinner the cookie, the more fragile.)
(4) Baking time (Same thing Econlady just said. The longer you bake, the firmer the cookies become.)
But if she over bakes the cookie can become more brittle. Also, let’s not forget this I’d for consumption and a dry over baked cookie doesn’t taste good. If you want to tell us your recipe we can tell you if it sounds incorrect.