chop up chocolate and add to a bowl with heavy cram and melt together then allow to cool. Blend softened cream cheese and butter together. Add Vanilla, powdered sugar and salt to cream cheese mixture. Add chocolate mix to cream cheese mix and blend. Add 1/4 cup Truvia and mix. Continue adding more truvia by TBS until sweetened to taste.
*note* if the mixture is allowed to chill completely, it will take a while for it to be spreadable.