- Place chocolate in food processor; process until chocolate is chopped.
- Combine cream and butter in 1-cup glass measuring cup and microwave at high 1½ minutes or until butter is melted and cream begins to boil.
- With food processor running, pour hot cream mixture through food tube, process until chocolate melts.
- Add liqueur and vodka, process until blended.
- Pour chocolate mixture into medium bowl, cover with plastic wrap and refrigerate overnight.
- Shape chocolate mixture into 1-inch balls and roll in walnuts.
- Store in airtight container in refrigerator.
- Let stand at room temperature 2 to 3 hours before serving.