Hot Buttered Rum

Make the Buttered Rum Batter: In a mixing bowl, beat butter and brown sugar until light and fluffy. Beat in ice cream and cinnamon, then spoon into a mason jar or resealable container. Store in freezer until mostly hardened, about 2 hours or until ready to serve. Make the Drinks: In a medium saucepan, heat cider until boiling, stirring occasionally. Remove from heat and pour into a pitcher or easy-to-serve container. Place about 2 tablespoons of buttered rum batter into each mug. Fill about 1/3 of the way up with rum, then top with hot apple cider. Stir before serving.