From the BBC:
When you visit Germany in the cold months you might come across a drink called Feuerzangenbowle - sometimes referred to as Crambambuli.
Ingredients
Some weeks before the Feuerzangenbowle is to be served, buy:
4 Oranges
1 Lemon (friends of a healthy lifestyle might want to add raisins and two apples)
1 bottle of rum (54%)
Peel all the fruit, separate the flesh and place the segments in a bowl. Add rum to cover the fruit, put a lid on the bowl, and let it sit until the day of the Feuerzangenbowle. If a weaker effect is desired, skip the bit about soaking the fruit.
For the Bowle itself you will need:
4-5 bottles of red wine (to avoid a storming hangover, it may pay not to buy the cheapest red available)
1 bottle of rum (54%)
4 cloves
1 stick of cinnamon
1 cone of sugar1
Method
Pour the wine into a big pot and add the cinnamon and the cloves.
Add the rum-soaked fruit, saving the rum3.
Heat the mixture to a temperature at which it starts steaming.
Place the Feuerzange over the pot and place the cone on it horizontally, not upright. Now use a large scoop to douse the cone with rum.
When the cone is nicely soaked, dim the light and ignite the sugar. You will be treated to a nice display of blue flames and of bits of molten, burning sugar dripping into the wine.
Continue to pour rum onto the cone until it's fully molten and has disappeared into the wine.
Remove the Feuerzange once all the flames have died down and serve the Feuerzangenbowle in mugs.
The mixture of hot wine, rum and sugar ensures an immediate feeling of warmth and relaxation for the consumer. This makes it the perfect drink for a cold winter night. Sometimes you will find Feuerzangenbowle being offered at Christmas markets. Don't try it, stick to the Glühwein ('mulled wine') instead.
A Word of Caution
Be prepared for igniting the cone of sugar. Flames might reach a height of 50cm so make sure the space above the pot is free. Most importantly use a metal scoop and never, ever pour the rum straight from the bottle. Also, be aware of the fact that the Feuerzange itself will be a little warmer than room temperature, so do not remove it with your bare hands.