Using a stand or hand mixer, add melted butter or margine and cocoa powder to a large bowl, mixing well.

Start adding powdered sugar, 1/2 cup at a time, alternating with splashes of milk, mixing well after each addition.

Continue adding powdered sugar and milk until you use all the sugar and reach desired consistency.

Mix in vanilla and salt.

Use icing immediately or store, covered, in the fridge until needed.

To use after fridge use: allow icing to come back to room temperature or place in microwave for 5 to 10 seconds, stirring well.