Chocolate Quark Cake Recipe

Remove the chocolate mixture from the heat, cover, and let it cool for about 10 minutes, or until it reaches room temperature.

Meanwhile, in a separate bowl, use a mixer to beat 1 1/4 cups butter on medium-high speed until it's smooth and creamy. Reduce the mixer speed to medium-low, then add half of the cooled chocolate mixture and 1 1/2 teaspoons vanilla extract, mixing until just combined.

Add the remaining chocolate mixture to the butter and beat until the frosting is smooth and creamy. Set it aside at room temperature for 1 to 2 hours, or until it has hardened slightly to a spreadable consistency. If you're in a hurry, you can refrigerate the frosting for about 30 minutes until it thickens; just be sure to bring it back to room temperature before you frost the cake.

Now, for the cake: Preheat your oven to 350°F. Generously grease three 9-inch round cake pans.

Cut a piece of waxed paper to fit the bottom of each prepared pan and place it inside. Grease the waxed paper, then dust the pans with 1/2 cup cocoa powder until they are well coated. Set them aside.

In a small heatproof bowl, pour 1/2 cup boiling water over the 1/2 cup cocoa powder. Stir until the mixture is very smooth, then set it aside to cool completely.

Melt the 2 ounces chocolate in a double boiler, stirring occasionally until it's smooth. Remove it from the heat once melted.

In a medium bowl, sift together the 1 3/4 cups cake flour, 6 tablespoons all-purpose flour, 1/2 teaspoon baking powder, and 1/4 teaspoon salt. Set these dry ingredients aside.

In a separate large bowl, beat the 3/4 cup butter until it's smooth and creamy, which should take about 5 minutes.

Gradually add 2 1/4 cups of the sugar to the creamed butter and beat until the mixture is well blended, about 5 minutes. Beat in the 1 egg and 5 large egg yolks, one at a time, ensuring each is fully incorporated before adding the next.

Beat in the cooled cocoa mixture until it's very smooth, scraping down the sides of the bowl as you go. Turn the mixer to medium-low and add the melted chocolate, beating until it's well incorporated into the batter.

Stir in the 1 tablespoon vanilla extract. Turn the mixer to low and add half of the sifted dry ingredients. Mix until just combined, then add the 1 cup quark and mix well. Add the remaining dry ingredients and beat until the batter is smooth and creamy, about 2 to 3 minutes.

In a separate clean bowl, use clean beaters to beat the 5 large egg whites on high speed until frothy. Gradually add the remaining 1/4 cup sugar and continue beating until the egg whites form stiff, glossy peaks, about 5 to 6 minutes.

Using a large rubber spatula, gently fold about 1 cup of the chocolate batter into the beaten egg whites to lighten them. Then, carefully fold this mixture back into the main chocolate batter, just until the egg whites are fully incorporated. Be careful not to overmix, as you want to keep the batter light and airy.

Divide the batter evenly among your prepared pans and bake them in the center of the preheated oven for 20 to 25 minutes. Avoid overbaking. The cakes are done when their tops just begin to crack and a toothpick inserted into the center comes out with a few moist crumbs clinging to it.