Preheat oven to 350 degrees F.

In a large bowl, melt the butter and the chocolate together in the microwave. Microwave for 30 seconds, stir, and continue to microwave until the chocolate is melted and smooth.

Add the sugar, egg, vanilla, salt, flour, and cocoa powder into the bowl and mix all the ingredients together well.

Pour into a greased 8x8 inch baking dish.

Bake for 25 to 30 minutes or until a toothpick inserted in the center of the brownies comes out clean.

Let the brownies cool completely before adding the mint layer.

In a medium bowl, mix all ingredients for mint layer together. Whip with the electric mixers or with a spatula until the consistency is smooth. Pour over cooled brownies.

Place the dish in the fridge after this step and let it cool for at least an additional hour.

In a small bowl, melt the butter and chocolate chips together in the microwave, stirring until smooth. Pour over the cooled brownies. Cool the entire pan for at least another hour before cutting and serving. Cut brownies with a clean sharp knife.