Scoop half of the ice cream into balls and place in the bottom of a large bowl or trifle dish. Layer with 1 1/2 cups banana slices then spoon 1/2 cup of the hot fudge sauce over the bananas. Spread half of the whipped topping over the hot fudge, then sprinkle with 1/4 cup walnuts and 1/3 cup cherries. Repeat the layers then cover and freeze for at least 6 hours. Remove from the freezer 10 to 15 minutes before serving.