Sprinkle garlic in bottom of a buttered 11- x 7-inch baking dish.
Whisk together whipping cream and next 6 ingredients.
Layer half of potato slices over garlic; top with half of cream mixture. Repeat procedure with remaining potato slices and cream mixture.
Bake, covered, at 350° for 40 minutes. Uncover and bake 30 more minutes or until gratin is golden brown. Let stand 15 minutes before serving.
Note: For testing purposes, we used canned chipotle peppers in adobo sauce. They may be found in the ethnic section of the grocery store.
