brown beef with finely chopped onion and taco seasoning and drain.
Sometimes I use onion powered if I don't have any onions on hand.
Layer Re-fried Beans(thin layers), beef mixture, enchilada sauce and shredded taco/nacho cheese. Placing a flour tortilla between each. (refried bean/tortilla/enchilada and beef/cheese/refried beans/beef and enchilada sauce/cheese). You can also add salsa as a layer if you like. I use a round casserole dish that is the size of the medium size tortilla and it works great for this dish.
Bake slow @ 250. After 30 to 40 minutes remove and add sour cream to top and place back in oven for 5 minute.