Preheat oven to 375 degrees. Saute first 4 ingredients lightly (add mushrooms t o pan last) in 2 tablespoons of butter. Turn off heat and mix in sausage, then set aside. Beat eggs, cream and seasonings together. Mix all ingredients togeth er, stirring in cheese. Pour into a 23 cm pie shell and brush shell edges with beaten egg white. Bake for 40 to 45 minutes. Cool 15 minutes before serving. Y ou may substitute one cup chopped ham for the sausage. Recipe from "One Million Recipes CD" busted by Judy R.