Rinse the fresh cranberries and remove any damaged ones.
Combine the cranberries and sugar in a bowl, and let it sit for about 30 minutes.
In another bowl, beat the softened cream cheese until smooth.
Fold in the whipped cream and vanilla extract into the cream cheese until well combined.
Stir in the macerated cranberries along with their juice into the cream mixture.
Add in mini marshmallows and chopped nuts, if using, and mix gently.
Chill the salad in the refrigerator for at least two hours before serving.