Cut Chicken into 1 inch cubes. In a 12 inch skillet cook Chicken in hot oil over medium-high heat for 4 – 5 minutes or till no longer pink. Remove Chicken; set aside. Add garlic, Mushrooms and Onion to skillet. Cook, uncovered, for 4 – 5 minutes or till liquid evaporates. In a bowl stir together sour cream, flour, ½ teaspoon salt and ¼ teaspoon pepper. Add sour cream mixture, milk, and broth to skillet. Cook and stir until bubbly. Cook 1 minute more. Add Chicken and Madeira or sherry; heat through. Serve over herbed biscuits. Sprinkle with thinly sliced green onions if desired. Makes 6 servings. Herbed biscuits: in a mixing bowl stir together 1 ¾ cup packaged biscuit mix, 2 tablespoons thinly sliced green onion, and ½ teaspoon crushed, dried oregano. Add ½ cup skim milk; stir just until do