To make cauliflower rice, grate the tops of cauliflower florets on the wide holes of a box grater, or in a food processor using the grater attachment. Cauliflower rice may also be purchased in the refrigerated produce section of many stores, or you can buy it frozen. If using frozen cauliflower rice, cook it in the skillet for a bit longer (about 6 minutes), until it is thawed and its water has evaporated before adding the flour. To make this gluten-free, dissolve 1 tablespoon plus 1/2 teaspoon of cornstarch into the milk instead of using the flour.