6 oz Semisweet chocolate *
4 tb Unsalted butter **
1/2 ts Vanilla extract
2    Egg yolks; lightly beaten
4 tb Unsweetened cocoa powder

*Note: Semisweet chocolate should be coarsely chopped. ** Unsalted butter
should be cut into small pieces. In a double boiler, melt the chocolate and
butter over simmering water. Remove from the heat and stir in the vanilla.
In a small bowl, gradually whisk the warm chocolate mixture into the egg
yolks. Cover and refrigerate until firm, about 1 hour. Shape level
tablespoons of the chocolate mixture into balls and then roll them in the
cocoa. Refrigerate the truffles.