In a large bowl, using an electric; mixer, mix together the butter and cream cheese on medium speed.
Add the vanilla and mix until the ingredients are fully combined.
Gradually at the powdered sugar at low speed until the ingredients are fully mixed.
Shape the buttercream into rounded balls, one inch in size. Place the balls onto the wax paper, loosely cover and refrigerate for two hours or overnight.
In a saucepan, melt the chocolate and shortening over low heat. Stir constantly and heat for three to four minutes, or until fully melted. You may also microwave the chocolate and shortening on 30-second intervals, stirring each time, until fully melted.
Take the buttercream balls and carefully dip them into the chocolate using a fork. Turn the buttercream balls over in the chocolate to fully coat, let the remaining chocolate drip off. Place them onto a waxed paper-lined baking sheet to let them set. Refrigerate buttercreams for at least half an hour before serving.