For ganache, place chocolate in a medium heat-safe bowl and place cream in a small saucepan over medium heat. Bring cream to a simmer, but do not let it boil. Pour hot cream over chocolate and let it melt for 2 minutes, then stir until chocolate is melted and mixture is smooth. Set aside in a warm spot.
Place biscotti in the bowl of a food processor and pulse until you have fine crumbs. Pour crumbs into a large mixing bowl. Add chopped fruit, nuts and salt to crushed biscotti and toss together.
Add vanilla extract to ganache and pour ganache over biscotti mixture. Stir until well combined and there is a uniform texture throughout. Press some cling wrap to the top of the mixture and refrigerate until firm enough to roll, at least 1 hour.
Once mixture has firmed up, scoop it from the bowl and, using waxed paper or parchment, roll it into a log about 3 inches in diameter and 12 inches long. Once it is a cylinder, roll it on the counter a few times to get it as round as possible.
Place log on a baking sheet and freeze until firm, at least 4 hours or overnight. Fifteen minutes prior to serving, remove log from the freezer. Roll in cocoa powder and cut into thin slices. Temper for an additional 5 minutes before serving.
Serves 10 to 12