This is my family's favorite cookie icing! It coats the cookies beautifully and leaves a smooth finish to your favorite homemade cookies!
Combine all ingredients and mix on medium to medium/high speed using a mixer.
Start out by adding only a couple tablespoons of milk. Add additional milk until your icing is the consistency you desire.
Optionally, you can add icing colors to your icing to make colorful cookies.
Use immediately. If you do refrigerate icing before using, be sure to mix again before use and add more milk if necessary.