In a large bowl cream together butter, powdered sugar, and almond extract. You can do this with a hand mixer or a stand mixer. Do this for 2-3 minutes until light and fluffy.
Once it is creamed together add in your cocoa powder and salt. Then adding one tablespoon at a time add in your milk. Mix after each tablespoon until you get a light and fluffy buttercream. You can add more than is recommended if you prefer.
Serve the buttercream on cupcakes, cake, brownies, and more!