* This may be substituted with a goat's milk cheese such as feta Peel and quarter the potatoes, cover with water, and cook until soft. Meanwhile, cook the chopped onions in melted butter until golden. Drain and rice the potatoes. Shred the cheddar cheese or crumble the bryndzia. Add the onions, cheese, salt and pepper to the potatoes, blending well. Allow to cool, stirring occasionally. This filling may be refrigerated for 2-3 days but not frozen. NOTE: Leftovers may be used to make breakfast cakes or a a filling for potato skins, stuffed in green peppers, or into rolled cabbage leaves.