Preheat the oven to 350 degrees F and prep a 8x8 inch baking pan with parchment paper.

In a large bowl, combine melted butter, eggs, vanilla extract, and coffee then mix together well.
Add the white and brown sugars to the mixture and whisk together well.

Sift cocoa powder, flour, and salt into the bowl and mix until combined. Add batter to pan and smooth to the edges. Bake for about 30 minutes or until the center is just set. You'll notice the center does not wiggle when the pan is moved.