Melt the vegan butter in a small bowl or 4 cup measuring glass. Once butter is melted, add the cocoa and whisk very well. Add the milk and mix again slightly. Put this in the microwave for about 1 min. 30 sec. to 1 min. 45 seconds. making sure the mixture is boiling. While the mixture is in the microwave, get out your mixer and put in the powdered sugar and vanilla. Once the other is done in the microwave, put it in the mixer and mix on high speed stopping to scrape the sides every once in a while until there are no more lumps of powdered sugar. Once you are done with this, it should be very creamy. Spread evenly over a warm cake. I like using the Super Moist Chocolate Cake from this website.
This frosting is super delicious and rich and has been used in my family for years! Enjoy!!!