Preheat the oven to 300 degrees.
Using a small sharp knife, make a shallow circle about 1/2 inch from the outer rim of the cheese. Using the knife blade at a very shallow angle, remove the top rind inside this circle, taking care not to pierce the outer rim of the rind.
Once the top circle of rind has been removed, place the Brie either in a shallow ceramic baking dish or on a piece of parchment paper on a cookie sheet.
If using two wheels of Brie, divide the cranberry sauce between the two wheels and spread to the outer circle of the rind. If using the larger wheel, spoon the sauce into the single circle and spread to the edges.
Bake the smaller wheels for 7 minutes, or until the cheese is soft but not oozing. Bake the larger wheel for 12 minutes. Remove from oven.
If using the cookie sheet, transfer the Brie carefully to a serving dish using a large spatula to support it. Allow to cool a bit.
Surround the wheel(s) of Brie with crackers and fruit slices. Delicious warm or at room temperature.