1 1/2 fluid ounces rum flavored liqueur
1 fluid ounce whiskey
2 fluid ounces lemon-lime flavored carbonated beverage
Lightly grease two 9-inch square or round cake pans.
Combine rum and whiskey. Pour into prepared pans. Freeze 1 hour in freezer or refrigerator, allowing liqueur to harden.
Remove from freezer. Mix lemon-lime soda and orange zest until blended. Pour over cream and frost. Chill in refrigerator.