In a small saucepan, heat heavy cream and butter over medium-low heat just until bubbling. Stir to prevent the cream from burning.
In a heatproof bowl, place dark chocolate chips in the bowl and pour heated heavy cream over top of the chocolate. Allow to sit for 10 minutes until the chocolate has melted slightly. Whisk until smooth. If the chocolate is not all melted, microwave the chocolate mixture in 15-20 second increments in the microwave.
Add whiskey and stir into melted chocolate
Allow mixture to cool and refrigerate until firm, overnight is best.
Place toffee bits in a shallow bowl or paper plate.
Scoop hardened chocolate with a melon baller or a tablespoon scoop. Roll into a smooth ball and roll in toffee bits. Keep refrigerated.