The following recipe is from the Baker Boulanger site belonging to Marcy Goldman and is her copyrighted recipe. She permits reproduction with proper accreditation.
A boastful title to be sure, but absolutely true. You just don't get cakes like this every day. Easy, moist, almost half a foot high, light but dense, non-dairy but very flavorful, stays fresh for days, can be frozen for months. When you think of a classic chocolate layer cake in an old-fashioned diner, this one fits the bill. My youngest son Benjamin expects this cake at least once a month...daily at Chanukah time. When I tested this cake, someone left a chocolate crumb covered napkin nearby with the words, (all in capitals) "THIS CAKE IS UNBELIEVABLE!" scrawled in that "midnight snack" scribble. A winner for any occasion. With its glittering array of gold-covered chocolate coins, this cake is a real treat for kids. For a bakery store look, garnish sides with chocolate sprinkles or jimmies and plant one solitary glace cherry in the centre. If you do not have cola on hand, you can substitute warm mild coffee.
2 cups granulated sugar
1 1/4 cups oil
2 teaspoons vanilla extract
2 1/2 cups all-purpose flour
1/2 teaspoon salt
1 1/2 teaspoons baking soda
1 1/2 teaspoons baking powder
1/4 teaspoon cinnamon
1 cup cocoa, measured then sifted
1 1/2 cups warm, flat cola soda
1/2 cup chocolate chips, melted and cooled
2 tablespoons shortening
3/4 cup unsalted butter or unsalted margarine
1 teaspoon vanilla extract
3/4 cup cocoa, measured then sifted
3 to 4 cups confectioners' sugar, measured then sifted
1/2 cup water, cola or half-and-half
20 to 30 gold chocolate coins
Colored jimmies or cake sprinkles
Miniature decorative plastic dreidels
Preheat oven to 350 degrees F. Lightly grease two 9-inch layer pans and line with parchment paper circles.
Cake: In a large mixing bowl, blend sugar and oil. Add eggs and mix until well blended and mixture is thick and lightened in texture.
In a separate bowl, stir together flour, salt, baking soda, baking powder, cinnamon, and cocoa. Fold dry ingredients into wet - and mix - drizzling in cola as mixture blends. If using an electric mixer, use slow speed and mix about 3 minutes, scraping sides and bottom once to incorporate all ingredients evenly. This is a thin batter.
Bake, on middle oven rack, 35 to 40 minutes, until cakes spring back when lightly touched.
Icing: Cream melted chocolate, shortening, butter and vanilla extract with cocoa and l cup of the confectioner's sugar. Add remaining confectioner's sugar and whip on high speed, adding in a bit of water, cola or half-and-half to get a light, fluffy consistency. If not using right away, re-whip before using. Add additional warm water to get correct consistency (a tablespoon at a time).
Decorating: Place one layer on a cardboard circle. Ice this with about 1/2 inch of frosting. Place top layer and ice cake - sides first. Coat sides with colored sprinkles. Garnish bottom edge with coins. Garnish top with coins - placing them either flat on top of cake or standing up (you may cut some of the coins in half to garnish border of top layer). Place a couple of miniature dreidels in center if desired or Chanukah candles (can be lit when menorah is lit).