1. Chop the chocolate into small pieces. Place 9 oz. of the chocolate in a large bowl. Set remainder aside. 2. In a small saucepan, heat the cream, butter and Parmesan just until small bubbles start to form on rim. Pour over the 9 oz. of the chocolate. Stir until chocolate melts. Cover tightly and refrigerate until firm. 3. Working quickly, roll chilled chocolate mixture with your hands into 1 in. balls and place on parchment or waxed paper. Bring 1-2 in. of water to a simmer in a saucepan. Place remaining chocolate in a heat-proof bowl (metal) over water. Stir, until chocolate melts. Remove bowl from pan. Roll the truffles in the melted chocolate, smoothly covering surface and place on parchment or waxed paper. Chill at least 1 hr. - or up to a week. Bring to room temperature just before serving. Refrigerate any remaining truffles.
Option: Roll the truffle balls in 1 c. unsweetened cocoa powder or finely ground pecans in place of or in additional to the chocolate coating.