Measure flour, sugar, cocoa, oil, eggs, buttermilk, baking powder, soda, and salt into a mixing bowl. Dissolve instant coffee in hot water, and add to mixing bowl. Beat at medium speed for 2 minutes until smooth; batter will be thin. Pour into prepared pans.

Bake for 30 to 35 minutes, or until an inserted wooden pick comes out clean. Cool in pans for 10 minutes, and then turn out onto racks to cool completely.

Frost cooled cake with Coffee Icing. After frosting, melt some semisweet chocolate baking squares or chips in a double boiler. Drizzle chocolate around top outside edges letting it run down sides, or over top of cake.