Preparation Put oven rack in upper third of oven and preheat oven to 375°F. Butter a 13- by 9-inch glass baking dish. Scatter garlic in bottom of baking dish. Peel potatoes and cut into 1/8-inch-thick slices. Layer potatoes in dish, sprinkling each layer with some of salt and pepper, then pour cream over potatoes. Bake, gently tamping potatoes down occasionally, until tender and top is golden brown (cream will be slightly thickened), about 45 minutes.