In a bowl beat eggs with broth, cream, salt and tabasco. Set aside. Prick bottom and sides of pastry shell and bake at 450� for 5 minutes. Remove from oven. Sprinkle pastry shell with 1/2 of parmesan cheese. Scatter 1/2 of broccoli, 1/2 of swiss cheese and 1/2 of scallions into shell. Repeat broccoli, swiss cheese, and scallion layers. Pour egg mixture over these ingredients and sprinkle with remaining parmesan cheese. Bake at 450� for 10 minutes. Reduce oven temperature to 325� and bake 25 minutes longer or until knife inserted in center comes out clean.