In a small bowl, whisk together flour, cocoa powder, and salt.

In a medium microwave-safe bowl, combine semi-sweet baking chocolate and butter.

Heat on medium for 30-second intervals until melted and smooth. Do not overheat or burn. Cool to tepid.

In a large mixing bowl, combine sugar and eggs, beating until combined.

In a slow drizzle, add the melted chocolate mixture to the mixing bowl.

Add the flour mixture and Guinness alternately, in 2-3 additions, beating until just combined.

Pour batter into a well-greased 9x13-inch pan.

Bake at 350 degrees for 25-30 minutes, or until a toothpick inserted near the center comes out clean.

Remove to a wire rack to cool completely. Meanwhile, prepare frosting.

In a large mixing bowl, beat cream cheese and butter until smooth.

Add powdered sugar and cocoa powder, and beat until combined.

In a small bowl, combine instant coffee granules and water, stirring until coffee is dissolved.

Add to mixing bowl, and beat until frosting is light and fluffy.

Frost the cooled brownies. Top with chocolate curls, if desired. Enjoy!