I'm looking at recipes for Hot Buttered Rum, as I have plenty of rum and it's cold out. Several of the recipes call for vanilla ice cream. Is that traditional? What is it for? Wouldn't it just cool off some of the water and possibly interfere with the steeping of the spices? Would it be better to just toss in some vanilla and extra sugar, or does the milk content actually change anything?
Example with ice cream: http://www.drinksmixer.com/drink5667.html
Example without: http://www.foodnetwork.com/recipes/emeril-lagasse/hot-buttered-rum-cocktail-recipe/index.html