Scrub 1 pound red beets. Place in a 1-quart baking dish or round cake pan and add 1/2 cup water—the beets should be sitting in a shallow puddle. Cover tightly with aluminum foil. Roast until tender and a paring knife slides through easily, about 1 hour. If you start to smell a burning-sugar smell while they roast, carefully peel back the foil, add more water, reseal the foil, and return to the oven. Meanwhile, make the dressing.