These brownies are moist, full of chocolate flavor and absolutely delicious. They're just like the ones the lunch ladies served at school lunch, but honestly this homemade version is even better!
Preheat the oven to 350 degrees F. Line a 9x13-inch baking dish with foil or parchment paper and spray with non-stick spray. Set aside.
In a large bowl, melt butter and add cocoa powder. Mix until combined.
Add the flour and sugar. Beat together then add eggs and vanilla. Mix just until combined. Don't overmix.
Pour batter into prepared baking dish and spread out evenly. Bake for 25 to 30 minutes or until toothpick inserted in center comes out clean. Remove brownies form oven and let stand for 15 minutes before frosting. You want the brownies still warm when you frost them.
FOR CHOCOLATE FROSTING: Beat together all the frosting ingredients until smooth. Pour and spread over warm brownies. Let cool completely before cutting and serving.