Pound steaks btween 2 pieces of waxed paper until 1/4 inch thick. Dredge in flour mixed with salt and pepper. In large skillet melt 1 tablespoon butter. Add steaks; brown about 1 minute on each side; remove steaks to a platter. Spread both sides with mustard and sprinkle with 1 teaspoon worcestershire sauce; set asside. In same skillet melt remaining butter. Add mushrooms and shallots; saute for 2 minutes. Add brandy and flame. Stir in boullion and remaining worcestershire sauce. Cook and stir until hot. Return steaks to skillet and reheat for 2 minutes. Sprinkle with parsley if desired. If wanted, substitute cubed or individual portions of beff round steaks, pounded.