From Cooks Illustrated. This specifically is their recipe for Hazelnut-Mocha truffles. Here are their notes: The problem with many homemade truffles is that they have a dry, grainy texture. There are three keys to creating creamy, silky-smooth truffles. First, start with melted chocolate. Melting the chocolate before adding the cream allowed us to stir—rather than whisk—the two together, reducing the incorporation of air that can cause grittiness. Second, add corn syrup and butter. Corn syrup smoothes over the gritty texture of sugar, and butter introduces silkiness. Finally, cooling down the ganache gradually before chilling prevented the formation of grainy crystals.
In step 3, letting the chocolate to rest on the counter for 2 hours allows it to “cure”, and contributes to its creamy texture. In step 5, running your knife under hot water and wiping it dry makes cutting the chocolate easier. In addition to the related variations, the truffles can be flavored with 2 tablespoons of your favorite flavored liqueur. We recommend using one of the test kitchen’s favorite baking chocolates, Callebaut Intense Dark L-60-40NV or Ghirardelli Bittersweet Chocolate Baking Bar for this recipe. If giving the truffles as a gift, place each one in a 1 1/2-inch candy cup liner and then place the truffles in a gift box. Keep refrigerated until giving.
Ingredients
GANACHE
2 cups (12 ounces) bittersweet chocolate, roughly chopped
½ cup heavy cream
2 tablespoons light corn syrup
2 tablespoons Frangelico (hazelnut flavored liqueur)
1 tablespoon espresso powder
Pinch salt
1 ½ tablespoons unsalted butter, cut into 8 pieces and softened
COATING
Dutch-processed cocoa
1 ½ cups finely chopped hazelnuts
Instructions
1. FOR THE GANACHE: Lightly coat 8-inch baking dish with vegetable oil spray. Make parchment sling by folding 2 long sheets of parchment so that they are as wide as baking pan. Lay sheets of parchment in pan perpendicular to each other, with extra hanging over edges of pan. Push parchment into corners and up sides of pan, smoothing flush to pan.
2. Microwave chocolate in medium bowl at 50 percent power, stirring occasionally, until mostly melted and few small chocolate pieces remain, 2 to 3 minutes; set aside. Microwave cream in measuring cup until warm to touch, about 30 seconds. Stir corn syrup, Frangelico, espresso powder, and salt into cream and pour mixture over chocolate. Cover bowl with plastic wrap, set aside for 3 minutes, and then stir with wooden spoon to combine. Stir in butter, one piece at a time, until fully incorporated.
3. Using rubber spatula, transfer ganache to prepared pan and set aside at room temperature for 2 hours. Cover pan and transfer to refrigerator; chill for at least 2 hours. (Ganache can be stored, refrigerated, for up to 2 days.)
4. FOR THE COATING: Sift cocoa through fine-mesh strainer into large bowl. Sift again into large cake pan and set aside. Transfer chopped hazelnuts to another large cake pan and set aside.
5. Gripping overhanging parchment, lift ganache from pan. Cut ganache into sixty-four 1-inch squares (8 rows by 8 rows). (If ganache cracks during slicing, let sit at room temperature for 5 to 10 minutes and then proceed.) Dust hands lightly with cocoa to prevent ganache from sticking and roll each square into ball. Transfer balls to cake pan with cocoa coating and roll to evenly coat. Lightly shake truffles in hand over pan to remove excess coating, then roll in hazelnuts. Transfer coated truffles to airtight container and repeat until all ganache squares are rolled and coated. Cover container and refrigerate for at least 2 hours or up to 1 week. Let truffles sit at room temperature for 5 to 10 minutes before serving.