This is something I came up with partly out of necessity (I had to make a cupcake topping and didn't have any heavy cream or icing sugar) and partly because I wanted my cupcakes to be very festive. This would work for frosting cupcakes or cake (I used vanilla, but any type of cake you like would be fine), or even on cookies. You could also substitute white chocolate chips instead of semi-sweet if you wanted a more pronounced eggnog flavor.