I was looking through some older threads and found this one. I have used an aluminum DO before and the only difference I have found is you have to keep turning it a 1/4 turn every few minutes to keep from getting hot spots. The lid also. I found a backpacking oven on a backpacking web site. I built it and it works great. It is made out of aluminum roof flashing, some 3/16 threaded rod and 2 pie pans. everything fits in side the flashing and you put 2 spray paint can lids on each end to transport it. Supertroll who designed it used it to cook a roast in. I have not done that but have made blueberry muffins in it by putting a pan inside and using those aluminum muffin cups. I also got a 9" flat TI plate and made a personal size pizza in it. It was real simple to make. The only problem was trying to find the thermometer that goes to 500 degrees. I live in a small town with not to many shopping options. I did find it on the web. He uses 2 thermometers, one in the roast to check the meat temp and another in the top to regulate the oven temp. These are the pictures he sent me on it.   (You need to Login or Register
PS. Don't try it first on your home stove if you have smoke detectors. The coating burns off the flashing and makes a lot of smoke and stink. Do your first heating outside on the grill or camp stove to burn off the coating. Your wife will like you better.