Remove skin from pheasant. In a large skillet cook pheasant in hot oil and butter over medium heat until brown, turning once. Place in a 2-quart rectangular baking dish. Sprinkle with salt and pepper. Add mushrooms, onion, and garlic to skillet. Cook and stir over medium heat for 2 to 3 minutes or until onion is tender. Stir in broth, Marsala, and orange peel. Pour broth mixture over pheasant in baking dish.
Using a slotted spoon, transfer pheasant and vegetables to a serving platter. Cover and keep warm.
Pour cooking juices into a medium saucepan. In a small bowl stir together sour cream, flour, and the 1/4 teaspoon salt. Whisk sour cream mixture into the pan juices until smooth. Cook and stir until thickened and bubbly. Cook and stir for 1 minute more. Spoon some of the sour cream mixture over pheasant and vegetables; pass remaining sauce. Makes 4 servings.