Line 2 standard baking sheets with wax paper. Set aside.
In a microwave safe bowl, melt together the chocolate chips and shortening. Melt on the 50% power or using the melt function in 30-45 second increments stopping to stir each cycle. Repeat until completely smooth. (Alternately, use a double boiler on the stovetop.)
Use a non-stick spatula to mix in the cashews and 1 cup toffee bits. Mix until all of the nuts are covered.
Use a Tbsp to drop clusters onto the wax paper at least 1-inch apart. Sprinkle the tops with the remaining toffee bits while the chocolate is still wet.
Allow to sit at room temperature until set or refrigerate to speed up the process.
Store in an airtight container chilled or at room temperature for up to 2 weeks. If chilled, bring to room temperature for serving.