Cacao Nib Gelato

Combine 1 1/2 cups heavy whipping cream, 1 cup whole milk, and 1/2 cup cacao nibs in heavy large saucepan. Scrape in seeds from 1/2 vanilla bean; add bean. Bring mixture to simmer. Remove from heat. Cover and let mixture steep 30 minutes. Uncover and return to simmer. Whisk 5 large egg yolks and 3/4 cup sugar in large heatproof bowl until mixture is pale yellow and slightly thickened. Gradually add hot cream mixture to yolk mixture, whisking until well blended. Return mixture to same saucepan and stir over medium-low heat until custard thickens and coats back of spoon when finger is drawn across and instant-read thermometer inserted into custard registers 170 °F, about 5 minutes (do not boil). Transfer custard to medium bowl. Cover and chill overnight. Whisk 5 large egg yolks and 3/4 cup sugar in large heatproof bowl until mixture is pale yellow and slightly thickened. Gradually add hot cream mixture to yolk mixture, whisking until well blended. Return mixture to same saucepan and stir over medium-low heat until custard thickens and coats back of spoon when finger is drawn across and instant-read thermometer inserted into custard registers 170 °F, about 5 minutes (do not boil). Transfer custard to medium bowl. Cover and chill overnight. Pour custard through fine strainer set over bowl; discard solids in strainer. Transfer custard to ice cream maker and process according to manufacturer's instructions. Transfer gelato to freezer container. Cover and freeze until ice cream is firm, at least 8 hours or overnight. do ahead Can be made 3 days ahead. Keep frozen. Bits of shell-roasted cacao beans; available at many specialty foods stores and from chocosphere. com.