Place chocolate chips and shortening in a medium heat-proof bowl.
In a separate large heat-proof bowl, put very warm water (100°-110° F/ 38°-43° C)
Carefully place bowl with chocolate into bowl with water; water should come halfway up side of chocolate bowl.
Stir chocolate and shortening constantly with dry rubber scraper until chocolate and shortening are melted, and the mixture is smooth. *Note: Do NOT get water into the chocolate. (If water cools, replace it with very warm water as directed in above steps; water temperature is important to success.
After chocolate mixture is smooth, remove chocolate bowl from inside water bowl.
With a fork, dip chilled candy centers into chocolate mixture, one at a time. Gently tap fork on edge of bowl to remove excess chocolate. Invert coated center on tray covered with waxed paper. Let stand until firm.
Store candies loosely covered in cool, dry place.
This should make enough coating for about 4 dozen centers