Make-Ahead: Wash sweet potatoes; prick several times with a fork. Arrange on paper towels in microwave oven, leaving 1" between each. Microwave at HIGH 22 minutes, rearranging potatoes once; let stand 5 minutes. Cool potatoes to touch; peel and cut into 1/2" slices. Arrange slices in a slightly overlapping spiral pattern 1 to 2 layers thick in a 12" round baking dish; set aside.
Meanwhile, combine cranberry sauce and remaining 6 ingredients in a saucepan; bring to a boil. Reduce heat; simmer, uncovered, 5 minutes. Pour cranberry mixture over sweet potatoes; cool. Cover tightly, and chill overnight.
When Ready to Serve: Remove from refrigerator; let stand 30 minutes. Uncover and bake at 350° for 30 minutes or until thoroughly heated and bubbly.