To make the frosting:In a medium-size pan, heat the cream and sugar

Stir until the sugar has dissolved

Add the chocolate & espresso powder and stir until it is thoroughly melted

Remove from the heat, cover, and let cool for about 10 minutes or at least to room temperature

Using a mixer, mix the butter on medium-high speed until it is smooth and creamy

Turn the mixer to medium-low and add half of the chocolate mixture along with the vanilla

Mix well

Add the remaining chocolate mixture and mix until smooth and creamy

Set aside until it hardens slightly, to become a spreadable consistency, 1 to 2 hours

(Or, you can refrigerate the frosting for about 30 minutes, or until it becomes thickened and spreadable

Bring it to room temperature before frosting

)To make the cake:Preheat the oven to 350*Generously grease three 9-inch round cake pans

Cut a piece of waxed paper to fit the bottom of each pan and place inside the pans

Grease the waxed paper, and dust the pans with cocoa powder until well coated

Set aside

In a small heatproof bowl, pour the boiling water over the 1/2 cup cocoa

Stir until the mixture is very smooth, and set aside to cool

Melt the chocolate in a double boiler

Stir occasionally until smooth

Remove from the heat

Into a medium-size bowl, sift together both flours, the baking powder, and salt

Set aside

In a bowl, beat the butter until smooth and creamy, (about 5 minutes)

Add 2 1/4 cups of the sugar and beat until well blended, (about 5 minutes)

Beat in the whole egg and egg yolks, one at a time

Beat in the cooled cocoa mixture until very smooth, scraping down the sides as you go

Turn the mixer to medium-low and add the melted chocolate, beating until well incorporated

Add the vanilla

Turn the mixer to low and add half the dry ingredients

Then add the quark, mix well, and add the rest of the dry ingredients

Beat until smooth and creamy, 2 to 3 minutes

In a bowl, using clean beaters, beat the egg whites at high speed

When frothy, add the remaining 1/4 cup sugar and continue beating until the egg whites form stiff peaks, 5 to 6 minutes

Using a large rubber spatula, fold about 1 cup of the chocolate mixture into the egg whites

Then gently fold that mixture back into the chocolate mixture, just until the egg whites are well incorporated

Do not overmix

Distribute the batter evenly among the pans, and bake in the center of the oven for 20 to 25 minutes

Do not overbake

Cakes are done when the tops are just beginning to crack and a toothpick inserted into the center comes out with a few crumbs clinging to it

Let cool on a rack for about 15 minutes

Remove the cakes from the pans and let cool completely on a wire rack

To assemble:Place the first layer on a serving plate and frost the top only

Place the second layer on top of the first and frost the top

Repeat with the top layer

Spread the remaining frosting along the sides until the cake is completely covered with frosting