2 cups smooth peanut butter
1 cup (2 sticks) butter, softened
1-1/2 pounds confectioners’ sugar
1 package (12 ounces) semisweet chocolate chips
1/3 cake paraffin wax

In a large bowl, combine the peanut butter and butter; mix until smooth. Gradually add the confectioners’ sugar, stirring until thoroughly mixed. Form the mixture into 1-inch balls, place on a waxed paper-lined rimmed baking sheet and chill for 1 hour.
In a double boiler over medium heat, or in a saucepan over low heat, melt the chocolate chips and paraffin wax, stirring until smooth. Stick a toothpick in the center of each peanut butter ball and dip each three-quarters of the way into the chocolate mixture, coating all sides except the top quarter. Place on the waxed paper-lined rimmed baking sheet and remove the toothpick. Using your finger, fill in the hole left by the toothpick.
After dipping all the peanut butter balls, cover, and chill or freeze until ready to serve.

From Mr. Food