Butter-washing spirits is a fascinating technique that imparts a silky mouthfeel and subtle buttery flavor to the alcohol. To do this, melt a desired amount of unsalted butter and combine it with your spirit of choice, typically in a ratio of 1 part butter to 4 parts spirit. Mix well and allow the mixture to infuse at room temperature for several hours, then freeze it until the butter solidifies. Once solid, remove the butter layer from the top. The remaining spirit will have absorbed some of the butter's rich flavors. This process works exceptionally well with spirits like bourbon, rum, and whiskey, creating a unique base for innovative cocktails.