Melt chocolate by breaking it into small pieces and placing it in a double boiler over medium-low heat or by microwaving and stirring for 20 seconds at a time. Once melted, cool so it is just warm to the touch.
Mix the melted chocolate and cinnamon into the butter until they are completely combined.
Pack tightly into a small ramekin.
If not eating immediately, store in the refrigerator and bring back to room temperature before using.
Notes
Yield is approximately 1/2 cup.If you're at a loss as to how to use this delicious butter, try putting it on crumpets, challah, cinnamon scones, or a piece of toast.