Preheat the oven to 350°.

Prepare 3 (8-inch round) cake pans by first coating them with vegetable oil spray. Cut out a circle of parchment paper the same size as the cake and place it into the bottom of each pan. Spray again.

In a medium bowl, combine the flour, baking soda, salt, and cocoa.

Use an electric mixer to combine the sugar and margarine until fluffy.

Add the egg yolks one at a time. Mix well.

Add the flour mixture in three parts, alternating with the buttermilk.

Stir in the black walnut flavoring.

Pour the batter into a large mixing bowl. Set it aside.

Beat the egg whites until stiff.

Fold the egg whites into the batter.

Divide the batter among the three pans.

Bake in the center rack of the oven for about 25 to 30 minutes or until a tester inserted into the middle of the cake comes out clean.

Cool the cakes in the pan for 10 minutes.

Continue cooling by removing each cake from the pan to a rack.

Remove the parchment paper.

For the frosting, use an electric mixer to combine the confectioners’ sugar, cocoa, melted butter, and salt.

Stir in the coffee and the black walnut flavoring.

Add just enough milk to reach the desired consistency.

Frost the cake as you wish.