It should not surprise you that I am also a Harry Potter fan. To get ready for the release of the next movie, "Deathly Hallows" I am working on a recipe for "Deathly Hallows Butterbeer."
I modified a recipe that is supposedly "historically accurate" (if its on the internet, it must be true!) that I found here. The beer I used was Dead Reckoning, a hoppy porter from Troegs. I thought it fit very well with the dark tone of the book as well as the name has "dead" in it. It is also a great beer by itself.
Here is what I did.
Heated up 3 bottle of the beer with the spices over medium heat (cinamon, ginger, cloves, nutmeg). While that came to a boil, I beat 5 egg yolks with 2 tablespoons of brown sugar and 1 tablespoon of white sugar (big deviation from the original recipe, but I didnt have 500 g of sugar). To avoid curdling the eggs, I beat them over a double boiler and slowly added in the hot beer mixture while whisking vigorously. Continuing to whisk, I added a stick of butter, small pieces at a time, waiting for a piece to fully melt before adding the next. The internet recipe says you can cut the beer but up to half using hot milk, but I only added a little bit (not sure of the exact amount).
I really enjoyed it (a non beer drinker complained that it tasted too much like beer) but I think a better cook could play with the spicing and make it better. At any rate, it is a good, beer centered replacement for egg nog come christmas time. And don't forget, when ordering a butter beer, say "Accio Butterbeer!"