There are a few cool tricks to this recipe, one of which I picked up from an old issue of Bon Appétit, one I learned from Robb Walsh, the great Tex-Mex scholar and restaurateur who runs El Real Tex-Mex in Houston, and a final one I learned by happenstance. First, for the thickening agent in the chile sauce, toast raw all-purpose flour in a pan until it is nutty and golden brown, then reserve it to stir in with the browned beef later in the recipe. Second, if you like truly melty cheese in the classic Tex-Mex tradition, use a mixture of American cheese, like Velveeta, with the Cheddar you use inside and on top of the finished enchiladas. Finally, if you’re fearful that a casserole of cheese, chili and fried tortillas may be a little rich for dinner, serve it with a bowl of tomatillo pineapple salsa on the side. The acidity provides a nice balance. (Note also that as with all recipes, but particularly this one, some planning and practice can get the preparation down to 60 minutes.)