To begin, clear a 3-foot-wide area of work surface. Line a large rimless baking sheet with waxed paper, securing it with tape. Fit a 12-inch pastry bag with a No. 1A decorating tip with a 1/2-inch round opening, or get a melon baler or a No. 100 ice cream scooper and some corn starch. Fill one or more small, shallow bowls with cocoa, hazelnuts or coconut.
To make the firm ganache: In the bowl of a food processor, pulse the chopped chocolate on and off until the pieces are the size of small granules. If you don't have a food processor, use a heavy French chef's knife to chop the chocolate very finely.
In a small, heavy saucepan, heat the cream over low heat until bubbles form around the edges of the pan. Pour the cream into a large bowl and let cool for about 1 minutes. Add the chocolate granules all at once, shaking the bowl gently to submerge them in the cream.
When the pieces are soft, begin stirring with a rubber spatula until the ganache mixture is smooth and thoroughly blended. If any pieces remain unmelted, briefly place the bowl of ganache over a pan or slightly larger bowl of hot water, stirring gently until they melt completely. Cover loosely and refrigerate, stirring occasionally, until a dollop of ganache dropped from the top of the spatula holds its shape-probably about 30 minutes to an hour. (Some couverture chocolates set faster than others.)
Spoon half the ganache into the pastry bag. Holding the bag perpendicular to the surface of the baking sheet, with the tip elevated about 1 inch, squeeze hard, lifting the tip slightly to allow a buildup of ganache about 3/4 inch in diameter. Stop squeezing the bag and pull it away in a quick, circular motion to break the flow. Repeat, making rows of mounds spaced about an inch apart, until all the ganache has been used.
Alternatively, use a melon baller or ice cream scooper dipped in cornstarch to scoop out the balls. Refrigerate until firm, about 30 minutes.
Roll each mound into a ball between your palms, then roll the ball into the cocoa, nuts or coconut to cover it completely. Place the truffle in a fluted candy cup. Repeat until all the ganache is used.
Serve at once or store refrigerated in an airtight contained for up to one month. Makes about 30 to 35 truffles.
Ingredients:
For the firm ganache:
NOTE: Couverture chocolate refers to cocoa butter-rich chocolates of the utmost quality, containing high percentages of chocolate liquor (sometimes more than 70 percent) and cocoa butter (at least 32 to 39 percent). Look for it in upscale gourmet shops and mail order catalogs under these brands: Cocao Barry, Callebaut, Peter's Chocolate and Valrhona
