This makes a lot, so give some to your friends and neighbors, too.
1 lb softened butter
1 lb light brown sugar
1 lb powdered sugar
2 tsp ground cinnamon
2 tsp nutmeg
1 qt softened vanilla ice cream
Combine butter, sugars, and spices. Beat until light and fluffy. Add ice cream, stirring until well blended. Store in freezer.
To serve, place 3 tbsp mixture and 1 generous jigger rum in large mug. Fill with boiling water, stir well, top with whipped cream and cinnamon stick.