Chocolate Ganache

2-1/2 lb.'s dark chocolate, chopped
1-1/4 cups heavy whipping cream
3 tablespoons Cognac

2/3 cup powdered sugar
1 tablespoon cognac

Chocolate Mayonnaise Cake

2- 8" round cake pans, greased and floured (9" pans can be substituted, the cake will not be as tall though).

2 cups all-purpose flour
3/4 cup unsweetened cocoa powder
1- 1/4 teaspoons baking soda
1/4 teaspoon baking powder
1-2/3 cups sugar
3 eggs
1 teaspoon vanilla
1 cup mayonnaise
1-1/3 cup water

edible gold powder

Simple Syrup

1/2 cup sugar
1/4 cup water
1/4 cup cognac
Boil sugar, water and cognac together until sugar dissolves.

Make the cake:

Preheat oven to 350 F

1. In a medium bowl, whisk together flour, cocoa, baking soda, and baking powder; set aside.

2. In large mixer bowl with paddle attachment beat sugar, eggs and vanilla until light and fluffy on high speed, about 3-5 minutes. Add mayonnaise, reduce speed to medium and beat a couple of minutes longer.

3. Add flour mixture to batter, alternating with water- starting and ending with flour. Pour batter into pans and bake for 30-35 minutes or until cake pulls away from sides of pan and middle of cake looks set. Leave cake in pan for 10 minutes, then turn out onto a cooling rack.

Make chocolate ganache:

1. In a large bowl over a double boiler, combine chocolate, cognac and cream. Whisk until chocolate is melted and all ingredients are combined.

2. Place about half the chocolate mixture in the mixer bowl and allow to cool for about 10 minutes. With the whisk attachment, beat on med-high speed gradually adding 2/3 cup sifted powdered sugar and an additional tablespoon cognac. Whip until very light and fluffy. The ganache will have hardened up and should be a spreading consistency. This will serve as the filling. Set aside until ready to assemble cake.

3. Whisk remaining ganache (what was left in the double boiler bowl) occasionally until it hardens up a bit. Set aside until the cake has completely cooled.

Assembling Cake:

Before you begin, make sure cake is completely cool- if you rush this process, everything will melt and you will have a gooey mess. (take my word for it- I've done it both ways!)

1. With a large serrated knife, split layers in half and set on a piece of parchment paper. Place the first layer on a plate at least 3 inches wider than the cake. Place about 1 cup of the whipped ganache in a pastry bag, set aside. Brush each layer generously with simple syrup as you add them to the stack.

2. The first layer will have whipped ganache as filling so spread about a 1/4" layer on. Top with the next layer of cake. Pipe a 1-1/2" tall "trench" of ganache along the perimeter of the second layer. Add custard or pastry cream making sure to contain it within the "trench" of ganache. Add fresh raspberries if desired. Top with third layer and spread with additional whipped ganache about 1/4" thick- the same as the first layer. Place top layer on cake and press slightly to seal cake. You are now done using the whipped ganache. To clarify- All ganache referred to now will be what was left in the double boiler bowl which was not sweetened.

3. Place about 1 cup ganache over cake and spread on top pushing all excess down the sides of the cake, this is the crumb coat. Any crumbs which come off the cake and stick to the icing will be covered up with the next coat. Place cake in the refrigerator for 15 minutes or until icing is set. (do not rush this part- it's so much easier to do it the right way!)

4. remove cake from refrigerator, add additional ganache to top of cake spreading with the spatula until cake is covered and smooth. By this time, ganache should be fairly stiff- place some in a pastry bag and pipe decoratively on cake.

5. Place a small amount of gold dust on your hand or small piece of paper. Blow the powder onto the cake until desired effect is achieved. Cakes filled with custard or pastry cream must be refrigerated.

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sourcE: Gourmet Girl