This is a HUGE recipe, but I love that - bake once for a crowd or fill your freezer with brownies for any occasion.
Preheat oven to 350 degrees. Grease a jelly roll pan (12 x 17 inch).
Beat eggs with a mixer in a large bowl until a pale yellow. Then add sugar, salt, vanilla and beat for 1 minute.
Spread into prepared pan and bake for 20-25 minutes or until brownies are set in the middle. Cool for 15 minutes and spread with frosting.
For the Frosting: Blend powdered sugar, butter, and cocoa along with enough milk to make the frosting a spreadable consistency. Somewhere between 1/4 to 1/2 cup of milk. You want a thick frosting that's barely spreadable. Spread over the brownies after they had cooled for 15 minutes. Keep spreading as the frosting melts making it even on the brownies. Allow brownies to continue to cool.
Finding the right kind of cocoa to use can be confusing. There's sweetened and unsweetened, baking cocoa...you name it. When you're looking for cocoa to buy, just look on the ingredients list and the only ingredient listed should be cocoa.
Yes. If you don't need a ton of brownies you can half this recipe and bake in a 9x13 baking dish.
Source: Real Mom Kitchen