This recipe is excerpted from the book Little Everyday Cakes by Nashvillian Candace Floyd. It's made in 2, 6-inch cake pans for 4 petite layers perfect for 4. You can also make it in 1, 9-inch cake pan for 2 layers. Or double the ingredients for a standard cake to serve 8. 

1. Preheat the oven to 350°F (180°C). Grease two 6-inch cake pans. Line the pans with parchment paper. Grease the parchment. Dust the pans with cocoa powder.

2. Combine the flour, baking soda and salt in a small bowl.

3. Combine the liqueur, coffee, and buttermilk in a small bowl.

4. Place the butter in a mixing bowl, and using an electric mixer at medium-high speed, beat until creamy. Add the granulated sugar, and beat until fluffy, about 4 minutes. Add the cocoa, and beat until combined. Add the eggs one at a time, beating well after each addition. Reduce the speed to low, and add the flour mixture and the buttermilk mixture a little at a time, beginning and ending with the flour mixture. Beat until just smooth.

5. Scrape the batter into the prepared pans.

6. Bake the cakes 25 to 30 minutes, until a tester inserted in the center comes out clean. Place the pans on a wire rack, and let the cakes cool 10 minutes. Remove the cakes from the pans, and return them, top side up, to the rack to cool completely.

7. To prepare the frosting, place the butter in a mixing bowl. Using an electric mixer at medium speed, beat until creamy. Add the confectioner′s sugar a little at a time, and beat until smooth. Add the coffee liqueur, a tablespoon at a time, beating until the frosting reaches the desired consistency. Add more sugar for a thicker frosting, or more liqueur for a thinner frosting.

8. Place one layer on a plate or cake stand. Top one with about a quarter of the frosting. Place the second layer on top, and frost the top and sides with the remaining frosting. Or cut the layers in half horizontally to form four layers, and frost only the tops of each layer.