2. Peel and core pears, then slice ¼-inch (1-cm) thick. Lay on a generously buttered baking sheet in a single layer. Roast in oven for 15 minutes. Turn slices and continue roasting 10 to 15 minutes or until edges are caramelized and brown. Arrange pear slices overlapping in a circle overtop Brie. Refrigerate, uncovered, for up to half a day.