FOR THE GANACHE FILLING:
12 oz. good-quality bittersweet chocolate
1 cup heavy cream
4 oz. (8 Tbs.) unsalted butter, at room temperature
1/4 cup good-quality liqueur (Cognac, rum , Grand Marnier)
2 lb. good-quality bittersweet chocolate
8 oz. Dutch-processed cocoa (optional)
Yields about 88 one-inch truffles.
Chop the chocolate for the ganache and for dipping. Using a serrated knife or the heel of a chef's knife, chop the 12 oz. of chocolate for the ganache into very small slivers and chips (no bigger than peanut-size). Put the chopped chocolate in a small stainless-steel bowl. For untempered truffles, chop the entire 2-lb. block for dipping and set aside. For tempered truffles, chop 1 1/2 lb. of the dipping chocolate. Using a chef's knife, chop the remaining 1/2 lb. into very small slivers, even smaller than the other piles, and set aside from the rest.
Make the ganache. Heat the cream in a small saucepan until it just comes to a boil, and pour it over the chopped chocolate. Using a rubber spatula, stir the chocolate and cream, starting with small circles in the center of the bowl. The chocolate center will become a viscous, shiny emulsion. Gradually stir in larger circles, bringing in more chocolate from the sides. Keep enlarging the shiny emulsified center until all the chocolate has been incorporated and there are no unmelted lumps. If the emulsion cools before all the chocolate has melted, briefly flash the bowl over a pan of hot (not simmering) water for a few seconds, being careful not to overheat the ganache and lose the emulsion. When there are no more lumps, continue stirring for one more minute to develop a smooth ganache. Don't over mix. Set the ganache aside to cool. Meanwhile, in a small bowl, beat the room-temperature butter with a wooden spoon until it is very soft, smooth, and creamy. When the ganache has cooled to room temperature and thickened noticeably, add the butter, in small pieces a few at a time, to the ganache. The butter should blend in without melting. Scrape down the sides as necessary, stirring until no butter bits remain. Add the liqueur gradually, whisking constantly to maintain the smooth emulsion. When you're ready to pipe, the ganache should be silky smooth and soft to the touch, almost like smooth peanut butter (but not as sticky). If you want to pipe the truffles immediately, chill the ganache in the refrigerator until it's cool but not firm, 10 to 15 min. If you're not piping right away, cover the bowl with plastic wrap and let it sit at room temperature until ready, up to one day.
Pipe and shape the truffles. Fit a pastry bag with a 1/2-inch tip and fold down the bag half way. Fill it one-third of the way with the ganache (or use a strong zip-top bag the corner snipped off to create a 1/2-inch opening). Pull up the sides, and twist the bag closed. Line two baking sheets with parchment or waxed paper. Holding the bag vertical, pipe the truffles on the baking sheet, aiming for marble-size drops. Don't worry if they're not perfect spheres, but do try for a vaguely round blob because the rounder the truffles are now, the easier they'll be to shape later. Refrigerate the truffles until quite firm, about 1 hour. Shape each truffle into a smooth ball by rolling them one at a time between the palms of your hands. Your palms will be covered in chocolate after rolling a few truffles. If you sense that the truffles are melting too much as you roll, dip your hands in ice water, dry them well, and then continue rolling. (If you want to smooth the truffles even more, refrigerate them for 30 min. and then roll them a second time.) Return the shaped truffles to the baking sheets and refrigerate for 1 hour, or until ready to dip.
Prepare your workspace for dipping and melt the chocolate. On a long work surface, set up your assembly line for dipping. If using cocoa powder for dusting, sift it into a shallow dish. Line a baking sheet with parchment or waxed paper. If you're right handed, set the cocoa to the farthest right side of the work area. (If you're left-handed, reverse this order.) Set the lined baking sheet to the left of the cocoa. The remaining space will hold the melted chocolate and the sheet of truffle centers, in that order. In a medium saucepan, simmer about an inch of water. Transfer the 2 lb. (or 1 1/2 lb., if tempering) of reserved chopped chocolate to a stainless-steel or Pyrex bowl that's large enough to rest over the water. Remove the simmering water from the heat, and set the bowl with the chopped chocolate over the pan of hot water. Stir the chocolate with a wooden spoon or heat-resistant rubber spatula until it's completely melted, being careful not to let steam condense on the melted chocolate. If you're not tempering, set the melted chocolate and the truffle centers on the work surface and skip directly to the dipping and dusting section. If you're tempering the chocolate, continue heating it until the chocolate thermometer registers between 120° and 125°F and proceed to the next series.
Temper the chocolate. Remove the bowl from the saucepan, wiping the bottom of the bowl dry with a towel, and cool the chocolate to 86°F. To bring the temperature down, add the reserved chocolate shavings, 2 Tbs. at a time, to the bowl, stirring gently after each addition. When the temperature reaches 86°F and the shavings no longer melt (you probably won't use all the shavings), very gently raise the temperature to between 88° and 91°F by setting the bowl over the pan of hot water for 10 seconds at a time and wiping the bottom of the bowl every time. To test if the chocolate is in temper, spread a teaspoon of chocolate on a piece of parchment or a spatula and let cool for a few seconds. The chocolate is in temper if it dries quickly and has an even gloss. If the chocolate has white streaks and is tacky to the touch, it is not in temper; start the tempering process again by melting the chocolate to 120°F (or just continue, knowing that the truffles won't be tempered). Keep the chocolate in temper by holding it between 88° and 91°F. To monitor the temperature, tape the thermometer to the bowl (or have a helper hold it). If the temperature in the center of the bowl drops too much, flash the bowl over the hot water in 10-second increments, until the temperature reaches 90°F. Set the tempered melted chocolate and the truffle centers on the work surface.
Dip and dust the truffles. Drop a truffle into the melted chocolate and spin it around to cover completely. Lift it out on the tines of a fork. Tap the fork on the sides of the bowl several times so the excess chocolate drips off and a thin chocolate shell forms around the truffle. Depending on the brand of chocolate and the thickness of the fork tines, you may have to tap 20 times or more. If using cocoa, tip the fork so the truffle falls into the dish of cocoa and continue with the remaining truffles. When the dish of cocoa is full of truffles, snap the dish back and forth and gently transfer the truffles to another plate. For truffles without cocoa, gently set the dipped truffle on the lined baking sheet, using a knife to nudge the truffle off the fork. If the fork has left an imperfection on the shell, give the truffle a quarter or half turn to roll it to the bottom. Chocolate will start to build up on the sides of the bowl, so just keep dipping in the center of the bowl and don't bother scraping down the sides. If the untempered chocolate thickens too much, or if the tempered chocolate falls to 88°F, flash the chocolate over hot water in 10-second increments to warm it.
Store the finished truffles. Store tempered truffles in a tin box or a plastic bag, and keep them in a cool, dry place. Untempered truffles must be stored in an airtight container and refrigerated. Remove them from the refrigerator an hour before serving, keeping them covered to prevent condensation.
From "Classic Chocolate Truffles," by Bill Yosses (Fine Cooking #31).