Place the beets in a heat proof baking dish, and season with salt and freshly ground white pepper. Pour about 1 inch (2.5cm) water in the bottom of the dish, cover, and bake the beets until they are soft through, 1 to 1-1/2 hours, depending on the size of the beets. Test for doneness by inserting a sharp knife blade into the center of the beet; you should feel no resistance. Remove the beets from the oven and let cool. As soon as they are cool enough to handle, trim and peel them.