In heavy saucepan, heat Candy Melts in sweetened condensed milk over low flame, stirring until melted and smooth. Remove from heat.* Stir in nuts and vanilla, if desired, then spread evenly into prepared pan. Chill 2 hours or until firm. Turn onto cutting board, peel off paper. Use cookie cutters to cut into shapes, or cut into squares. Store in airtight container, at room temperature.
* For microwave, heat Candy Melts and sweetened condensed milk in 2 qt. glass container on high power 2½-3½ minutes, then stir until melted and smooth. (Note since microwaves vary in wattage and power output, cooking time may need to be adjusted.)
*This recipe also works with White Candy Melts or Dark Cocoa Candy Melts.