Grease a 9 x 13 inch baking pan. In a mixing bowl, melt butter or margarine, and then stir in cocoa.
Add in sugar and eggs to the mixing bowl and stir together.
Add in vanilla, flour, nuts and salt and beat together well.
Spoon batter into the prepared pan. Bake 25 to 30 minutes, or until cooked through.
Mix the frosting ingredients together and spread over the hot brownies and serve.
You can also let the brownies cool and then frost. This way the frosting is thicker.
Notes
Brownies should be wrapped tightly with plastic wrap and aluminum foil before freezing to maintain their freshness and prevent freezer burn. You can also tuck them in an airtight container and slide them into the fridge. Consume within 3 to 4 days, if you choose not to freeze them.