ROASTING PANS don't seem like a particularly interesting topic for discussion until yours bends double while it's full of hot fat. This happens sometimes when a flimsy pan has been in the oven for an hour or two, then gets taken out and cooled quickly. Roasting pans of thin-gauged metal and no reinforcement around the rim, while they don't literally bend double, do sometimes warp dramatically enough to make them dangerous.
And there are other problems with roasting pans. Some of them have handles -- or worse, no handles -- that make them impossible to move without putting your life and that of your roast in danger, or at least dragging the potholder in the drippings. Some are so shallow that before you know it a roasting duck sends its molten fat over the sides and down into that dark kingdom at the bottom of the oven. And, while beauty is not the first thing on your mind when you go looking for a new roasting pan, there's no reason why a good one should be ugly.
The classic, the ne plus ultra, the roasting pan that has taken the heat in restaurant, hotel and some home kitchens practically forever, is a boxy-looking, heavy-gauge aluminum pan with handles that stand high and at the ready. In some ways the handles are the best part. Unlike many roasting pans, they assume that you will actually have to lift the pan at some point, and that the pan will have something fairly heavy in it. Each handle is generous enough to allow a potholder-mittened hand securely inside.
The pan is made of plain aluminum, not anodized. This fact will arouse trepidation in some cooks about the possibility of the pan's reacting with foods like wine or tomatoes, but that is not really a problem. First of all, you will not be making fine little bearnaises in this pan. That would be like trying to set diamonds with your sledge and wedge. Second, what you will get if you add tomatoes, for instance, to your roast is a darkening of the aluminum and nothing more. Deglazing the pan with wine likewise presents no taste problem.
So don't worry about reactions, unless you can't stand discoloration and require your roasting pan always to be shiny, in which case you should stick with stainless steel, and possibly not cook anything in it either. There are some fine stainless steel pans on the market of a gauge heavy enough to prevent warping, but stainless is such a bad conductor of heat that you will likely find a burned ring on the bottom of such a pan when you try to make gravy with the pan drippings. The only advantage stainless has is that it can be kept sparkling.
The heavy aluminum pan comes in several sizes, including a smallish one that will hold two small chickens or a large beef roast and can easily double as a lasagna pan. It measures about 10 by 14. The next size, which is just big enough to hold a whole leg of lamb and a dozen small potatoes, measures about 12 by 15, and the largest, for your biggest turkey, 14 by 18. They are all a generous four inches deep. When deciding about sizes, remember that the ideal roasting pan size is always just slightly larger than the thing you are roasting. The juices of a two-pound pork roast cooked in a turkey-sized pan will quickly evaporate and/or burn on the bottom.
These pans are expensive. The medium-sized, "hotel-weight" pan will set you back about $50. There is a lighter weight (lighter gauge) pan of the same design that is not quite so serviceable-looking but is still several cuts above the average. These pans are about 50 percent cheaper than their heavier-gauged cousins, and they are certainly the thing to buy if you won't be using the pan very frequently or if the simple sight of a 3/16-inch-thick roasting pan doesn't make your heart quicken.
And there are other, more specialized possibilities. One is an oval, carbon steel pan that is essentially a gratin-dish shape. An argument could be made that oval is the sensible shape for roasting pans, since rare is the piece of meat that comes in a perfect rectangle. The steel pans will heat up and cool off quickly, making them better for browning the roast or making the gravy than for roasting. Enameled cast iron gratin dishes make nice little roasting pans, too, but if they are used frequently as such you'll have to resign yourself to some grunge and discoloration in the cream-colored interior.