* You can use butternut, acorn or pumpkin squash. Serve cupfuls of this elegant, colorful soup as a starter to a fall menu. For a creamy version, add light cream or buttermilk when reheating the soup before serving. In a 2 quart casserole, combine butter, onions, garlic and gingerroot. Microwave at High for 4 to 5 minutes or until onion is very tender, stirring once. Blend in flour; stir in chicken stock and squash. Microwave at High for 7 to 9 minutes until boiling and thickened, stirring once. Puree in a food processor or blender until smooth. Add orange juice and rind; season with salt, pepper and nutmeg. Thin with additional stock, or add cream or buttermilk. Microwave at High for about 2 minutes or until very hot. Ladle into heated soup bowls and sprinkle with chopped parsley. By Johanna Burkhard, From The Gazette, 91/11/13.