1.Preheat oven to 350 degrees. Prepare a 9″ x 13″ baking pan with butter/oil and 1 tbsp. cocoa powder. Coat evenly and shake off extra cocoa powder.
2. Pour one cup coffee into a measuring cup set aside to cool or mix the instant coffee with the 1 cup hot water. Cool.
3.Whisk flour, sugar, cocoa powder, baking soda, baking powder and salt in a large bowl.
4.Add to the flour mixture: eggs, buttermilk, oil, chocolate extract, and coffee. Beat for 2 minutes on medium speed. Pour the thin batter into the prepared pan.
5.Bake for 30 to 40 minuted, or until toothpick inserted in the center of the cake comes out clean. Cool completely.
6.When served sprinkle confectioners sugar on top if you desire for a little extra sweetness. Enjoy!