Serious Eats - seriouseats.com

Esmeralda - I'm reading thru the comments and it doesn't seem your original question was ever question as to the difference between using granulated vs. confectioners sugar in the dough. I've been making these cookies since I was a kid, using my Mexican grandmothers recipe. Using the confectioners sugar gives you a flaky, crumbly cookie. It does hold up to the tossing in sugar afterward, but you have to handle them delicately (think almond cookies). I prefer to use this kind of sugar because they do, literally, melt in your mouth. Using granulated sugar will give you a harder cookie - not tough, just harder. These hold up better for mailing and it's a texture that most people are used to in cookies. My father prefers the harder ones to dip in milk so I make a few batches of the granulated sugar ones for him and the rest I make with confectioners sugar. Also, instead of the 1 cup of butter I use 1/2 butter, 1/2 lard - no salt since I use salted butter and I add a 1/2 teaspoon of almond extract to the dough. I literally can't stand the smell of almonds for a few weeks after baking 20 batches of these but they're always a hit!