Using a coffee grinder, grind the sweetener until a fine powder to resemble powdered sugar. In a large mixing bowl, beat cream cheese, butter, peanut butter and vanilla until smooth. Beat in sweetener. Form rounded tablespoonfuls into egg shapes. Place on waxed paper-lined baking sheets. Chill for 30 minutes.
To make the chocolate coating, Place the butter and chopped chocolate in a double boiler (or in a heat safe dish over a pot of boiling water). Stir well until just melted (don't burn the chocolate!), add in the cream, and sweetener. Stir until smooth and thick. Dip eggs until coated; place on waxed paper to harden. For more decorative eggs, place about 1/4 cup melted chocolate in a small plastic bag. Cut a hole in the corner of the bag; pipe chocolate over tops of eggs. Store in the refrigerator. Makes 30 eggs.