Combine sugar, brandy or pineapple juice, sour cream, butter, marshmallows and salt in a heavy saucepan. Stir over moderate heat until sugar is dissolved. Place candy thermometer in mixture and boil about 10 minutes to 234 degrees or soft ball stage. Remove from heat; pour 0.75 cup of the hot mixture into a 1 litre measure and add semi-sweet chocolate; stir until the chocolate is melted. Quickly stir in walnuts. Turn into a buttered 9x5 inch loaf pan and spread level with back of spoon or spatula. Set the pan with remaining syrup into shallow pan of boiling water; add white chocolate and cherries and stir until the chocolate is melted. Turn into pan with chocolate mixture and quickly spread level; let stand until set before cutting into squares. Recipe by Ruth Snider; as published in the Cedar Rapids Gazette 19Nov94