Preheat oven to 350°F. Line a 9x13 baking dish with parchment paper, set aside.
Place butter in a large microwave safe mixing bowl, melt completely. Add sugars, cocoa, vanilla and eggs. Whisk to combine well. Add remaining ingredients. Whisk until completely combined, but do not over mix.
Pour into prepared baking dish. Bake for 20 minutes or until a tooth pick comes out clean. Allow to cool completely before cutting.