Grease a 8 x 11-inch pan. Line with parchment paper. Grease the parchment.
In a double boiler, melt together the butter, chocolate, cocoa and coffee granules.
In a big bowl, whisk together the eggs. Add the sugars, vanilla and salt.
Mix in the melted chocolate mixture. Fold in the flour until just combined.
Pour the batter into the prepared pan.
Bake 34-35 minutes, just until a toothpick inserted in the center comes out clean. Take care not to over-bake.
Cool completely. Chill in the refrigerator.
Using the parchment as a sling, lift the brownies out of the pan. Place them on a cutting board. Use long, sharp knife to cut into squares.
Notes
I use chocolate that's 70 percent cacao. To me, it's the perfect balance of bitter and sweet. Use whatever degree of bittersweet suits your taste, but always use good-quality chocolate (and good-quality butter).