Place potatoes in a small saucepan covered with cold water and a pinch of salt. Bring to a boil over high heat, and cook for 1 1/2 minutes. Remove from heat and drain.
Heat heavy cream in a medium saucepan with garlic over medium-low heat until reduced to 2 cups, about 30 minutes. Add drained potatoes, salt, pepper, and nutmeg. Cook over medium heat, stirring occasionally, until potatoes are tender, about 15 minutes.
Remove garlic and divide cooked potatoes between 2 (6-inch round) gratin dishes or 1 large gratin dish. Sprinkle with cheese, and place under broiler until golden.
(c)2003 Martha Stewart Living Omnimedia, Inc. All Rights Reserved.