Place oven rack to lower-middle position and pre-heat to 350 degrees. Grease (or use cooking spray) an 8-inch square baking pan. Line with 2 pieces of parchment paper, one crossing over the other, with sides coming up beyond the pan. Grease parchment paper and set aside.

In a double boiler melt the chocolates and the butter, stirring until smooth. Whisk in the cocoa and coffee powder. Set aside to cool.

In a medium bowl whisk together the eggs, sugar, vanilla, and salt. Whisk the chocolate mixture into the egg mixture, then using a rubber spatula, fold in the flour.

Pour mixture into prepared pan and bake for 30-35 minutes, until a toothpick inserted in the center comes out clean (or with a couple tiny crumbs).

Place brownies on a wire rack to cool completely for at least 30 minutes. Using the excess parchment, pull the brownies up out of the pan and place back on the wire rack to finish cooling. Once cooled place on a cutting board.

Cut into 4 columns each way, to make 16 pieces.