1 (1 lb.) box confectioners' sugar
3 sq. unsweetened chocolate
1/2 c. butter
1/3 c. evaporated milk

Melt chocolate and butter in top of double boiler. Add to sugar using enough milk to make the consistency you want. (Start with less than 1/3 cup milk, then add as needed.) Beat with mixer until creamy.

For brownies, make frosting a bit thinner than usual. Prepare about 10 minutes before brownies are done, then frost when they are baked and marshmallows have been sprinkled over top of brownies.