Wash and slice mushrooms, stems and all. sauté over medium heat in butter, stirring occasionally, for 10 minutes. Stir in flour, milk, bouillon cube dissolved in hot water, grated onion, salt and pepper.
Cook, stirring, until thick. Pour about 1/2 cup of sauce into each of 6 individual ramekins or casseroles (sauce should be about 1" deep). Break an egg into each ramekin. Slip a spoon under egg and press into sauce so that egg will sink lightly. Remove spoon. Bake in a 350° F oven until eggs are cooked to desired doneness, about 20 minutes.Servings: