Add the cream cheese, cream and vanilla to the yolks and thoroughly mix. Add the cocoa, sugar and salt and continue to mix until well incorporated and smooth. A food processor will simplify this process.
Cocoa and sugar amounts may need to be adjusted slightly depending on personal taste and the percentage cocoa used. Accordingly, the amount of heavy cream may also need to be adjusted.
Watch how easy it is to make Chocolate Deviled Eggs.