Lightly butter a 9x12 glass baking pan. Spread the bread with butter and cut into 1/4 inch cubes, leaving on the crusts. Cook sausage well and drain. Layer the bread cubes in the pan. Top with half the sausage, 1 cup of cheese. Repeat the layers until all is used. Beat eggs until light and lemon colored. Beat in milk, wine, garlic powder and mustard. Pour over pan. Cover and refrigerate 8 hours or overnight. Uncover and bake at 325~ for 1 hour or until lightly browned. Top with remaining cheese and green onions. Let stand 5 minutes before serving.