This is a recipe for a Czech barley casserole that is traditionally served on Christmas Eve but is also good as a side dish. Cook the onion in the butter until translucent. Wash the mushrooms until free from grit. Add the barley (or barley grits, mushrooms, salt and water to the onions and cook, uncovered, until the water has evaporated, stirring frequently. (Mixture will be very thick.) Add the remaining ingredients. Place in a greased casserole or baking dish and bake at 180ºC or 30 to 35 minutes. I usually cut this recipe in half unless we are having a really big crowd. It also freezes well.