1/4 pound (18-20) peeled whole roasted chestnuts
1/2 cup milk
1/3 vanilla bean, split
2 1/2 ounces semisweet chocolate, coarsely chopped
1 tablespoon light corn syrup
2 to 3 teaspoons cognac
1 pinch salt
1 tablespoon + 2 tsp unsweetened cocoa powder
In a small heavy saucepan, combine the chestnuts and 1/2 cup of water. Cover and simmer over very low heat until the water is evaporated but the chestnuts are still moist, about
Stir in the milk. Scrape the seeds from the vanilla bean into the mixture and add the bean. Cover and simmer over very low heat until the chestnuts are very tender and the milk has been
reduced slightly, about 15 minutes. Remove the pan from the heat; stir in the chocolate, cover and set aside to melt, stirring occasionally, until the chocolate is creamy, about 3 to 4 minutes. Remove
and discard the vanilla bean.
Combine the chocolate-chestnut mixture and the corn syrup in a food processor. Process, scraping down the sides occasionally, until the mixture is perfectly smooth, about
2 minutes. Add the cognac (to taste) and the salt; process for another minute. Transfer the truffle mixture to a bowl, cover and refrigerate until firm.
Place the cocoa powder in a medium bowl. Scoop
up 2 teaspoons of the truffle mixture and roll it into a rough ball with your fingers. Repeat with the remaining truffle mixture. Working with a few at a time, toss the truffles in the bowl of cocoa
powder to coat thoroughly. Transfer them to a plate as they are finished, then sift the remaining cocoa powder over them.
The truffles will keep for several weeks refrigerated in a tightly sealed
container. If the truffles absorb the cocoa powder, sift a little more over them just before serving.