François Nonnenmacher (EN) | FR

Every year at this period of time I make chocolate truffles. Pretty good ones am I told. I think it's as worth as a web advice, so here is the recipe:

Chocolate Truffles (the original, short version)

250 g of dark chocolate
100 g of fresh butter
1 tablespoon of whiskey or rhum
Cocoa powder (pure, preferably Van Houten)

Melt the chocolate in a bain-marie without stirring then add the butter and stir continuously until the mix is smooth. Remove from heat and add the alcohol.
Let rest in a cold place but not in a fridge during at least two hours or for a night.
With a teaspoon, take small pieces of chocolate and work them quickly with your hands to form a ball then roll it in cocoa powder. Let the truffles harden, in the fridge this time, before placing them in a box or in whatever wrapping of your choice.

The hacker's version, with tricks and 25 years of experience:

Prepare the butter first, cut it in small pieces with a knife and let it get soft (it must not be liquid). Break the chocolate in small pieces and place in the bain-marie with one tablespoon of water. The trickiest part is to get the chocolate to melt without stirring at all, otherwise you'll get pieces of hard chocolate in your truffles. You can push gently on top of the chocolate pieces to make them drip into the molten chocolate but you really need to trust me about not stirring until it's completely melted! The bain-marie needs to be just frémissant, the melting needs to be gentle, otherwise the chocolate will burn, but not too long, otherwise it'll burn too. You can replace the suggested alcohols with anything you feel with go with chocolate (I tested Kirsch, Grand Marnier and Cognac successfully). Stir well when adding the alcohol.

Forming the truffles and rolling them in cocoa can be a funny and messy experience and I'll leave that for your pleasure. If you're a productivity freak, you can pour the liquid chocolate into a square plate that you have previously recovered with an aluminum foil. Once the chocolate is solid, cut it into little cubes and roll them in the cocoa (you can place them in a deep bowl with cocoa powder and shake them). The only trick is to find a plate of the right size so that your truffles will be square.
Square truffles are geeky and one of my specialties.

If you keep your truffles in the fridge, you can keep them as long as you would keep the butter (that's why you want real fresh butter).

Enjoy!