Mix the peanut butter, powdered sugar, butter, and vanilla until smooth. You'll need to use your hands and really work the dough until it all comes together.
Chill the dough and then form the dough into balls about the size of a buckeye (if you're not familiar with that nut, it's a bit smaller than a ping pong ball). Place the balls on cookie sheets and chill.
Cut the parafin wax and the baking chocolate into small pieces for quickest melting.
Melt the chocolate chips, baking chocolate, and parafin wax in a double boiler. If you don't have a double boiler, melt over low heat and stir constantly.
Working with one tray of peanut butter balls at a time, insert toothpicks into the tops of the balls, then pick up an individual ball by the toothpick and dip the ball in the chocolate. Don't totally submerge it - you want the top to be chocolate-free. Place the dipped ball on waxed paper. Repeat this process for the rest of the balls.
Remove the toothpicks from the balls.
Refrigerate any buckeyes you aren't going to eat immediately.