Instructions

1. Add the butter (it should be “slightly softened” which is somewhere between straight out of the refrigerator and room temperature) and the Kahlua Rum and Coffee Liqueur to a mixing bowl. If you want a little bit of a stronger flavor you can add more later in the process.  But remember, the flavor will definitely grow stronger over time as the flavor melds with the other ingredients.
2. Mix the butter and the Kahlua together on medium speed until thoroughly combined (about 2 minutes.) 
3. Use a spatula to scrape the butter mixture down from the sides of the bowl.  
4. Measure 1 pound of Powdered Sugar.  If you don’t have a food scale, the equivalent is 4 cups. 
5. Add the powdered sugar to the mixing bowl.  
6. Start your mixer (or electric beater) on the lowest setting. Keep on low until the butter and sugar are incorporated (about 30 seconds), remove the dishtowel, and scrape down the sides of the bowl. Increase the mixer speed to medium-high and mix for 30-45 more seconds until the frosting starts to be light and fluffy.
7. If the frosting is too thick at this point, add another teaspoon of Kahlua and mix again.
8. Taste your frosting! You are trying to determine if the consistency is correct or if it needs a tiny bit more Kahula. Depending on how it tastes, you will take the next step.  If the frosting has the right taste but is too thick, add some milk and mix again to check to see if it is now the right consistency.  How much milk? That depends on the state of your frosting. A good rule of thumb is to add the milk a teaspoon at a time.