Place chops on broiler rack 5 to 6 inches from heating element; broil about 8 minutes on each side.
Melt butter in a heavy saucepan over low heat; add flour, stirring until smooth. Cook 1 minute, stirring constantly. Drain mushrooms, reserving liquid. Gradually add mushroom liquid and beef broth to flour mixture; cook over medium heat, stirring constantly, until thickened and bubbly. Stir in salt and pepper.
Slice mushrooms in half, and add to sauce. Cook over low heat 10 minutes. Serve sauce over chops. Garnish with parsley.