I stole this technique from Alton Brown. I didn't try it at home first, just plunged in and used it as a side dish for a catering job. I cooked and delivered it, and a daughter-in-law's mother was one of the servers. She reported back that the church ladies loved it so much, they came back for seconds; for the first time in recorded history, the carrots ran out before the meats (ham and turkey). I tried it with yellow sweet potatoes next, then orange ones, and the same thing happened--vegetables POOF! disappeared. I dunno--they're good, but I'd rather fill my plate with the expensive stuff on the buffet table.
Here's Alton's recipe:
In my version, I add a teaspoon of grated fresh ginger and omit the chili powder and most of the parsley. Sometimes I omit the parsley entirely and sprinkle on some thyme.
For sweet potatoes, I peel and slice them about half an inch thick, then pour over enough ginger ale to cover and sprinkle in a teaspoon or two of grated ginger. If the sweet potatoes are done before the ginger ale is reduced, I put them into a casserole and boil down the soda until it's syrupy, and then I enrich it with a goodly dollop of butter.
Have fun with this--I've tried 7-Up, Sprite and Mt. Dew, too, but I like ginger ale the best. I think I'll try sweet potatoes with Dr. Pepper sometime before Christmas. It sounds good to me.