First Communion Open Book Cake (Chocolate Ganache & Mascarpone Filling)

My cake baking challenge for this weekend was to make a first communion cake for our friends’ sweet little girl. I decided to bake an open book cake with two layers of filling – first layer with chocolate ganache & sour pitted cherries and the second one with a mascarpone cheese  filling. It was a great experience decorating this cake and for a first attempt at making a book cake, I think it turned out nice. It took me some time to make it but the smile on Alessia’s face when she saw the cake was worth all the effort :). Congratulations on your First Communion Alessia!

Time: I lost track of time but baking the cake & making the fillings would take around 1.5 hrs + chilling time… decorating the cake, a few more hours
Servings: 26-30             

Ingredients:

For cake:

• 12 eggs
• 12Tbsp water
• 18 Tbsp all-purpose flour
• 6 Tbsp cocoa powder
• 24 Tbsp sugar

I used a 10 x 15 x 3 inch baking pan, greased with butter and lined with parchment paper.

For  chocolate ganache filling:

• 300 g semi-sweet chocolate
• 300 ml whipping cream
• 250 g red sour pitted cherries in syrup, drained

For mascarpone cheese  filling:

• 475 g mascarpone cheese
• 500 ml whipping cream
• 275 g sugar (1 ¼ cups)
• 50 g white chocolate, grated

For syrup to moisten cake:

• 500 ml boiled water
• 12 Tbsp sugar
• 2 Tbsp rum extract

For decorating cake:

I used honey fondant (see my post on How to Make Honey Fondant) to cover the cake and make the decorations. You will need 1.5 times the quantity indicated in my post. You also need pink food coloring.

Directions:

Cake:

Beat egg whites and water with an electric mixer until stiff peaks form. Add sugar and beat until dissolved. Fold in the egg yolks.

Combine flour and cocoa powder.

Carefully blend in the dry mixture until just combined.

Preheat oven to 180°C (350°F). Pour batter into the pan and bake for about 35-40 minutes, or until brown (you can insert a toothpick in the centre and if it comes out clean then it’s ready).

Mascarpone Cheese Filling:

Bring 2/3 of the whipping cream to boil in a saucepan. Add grated white chocolate and stir until smooth. Add remaining whipping cream and sugar and stir until sugar dissolves. Chill until cold, at least 2 hours or overnight (cover before refrigerating).

Add mascarpone to chilled mixture and using an electric mixer beat on low speed until blended and smooth. Increase speed to medium-high; beat until mixture is thick and medium-firm peaks form when beaters are lifted, about 2 minutes (do not overbeat or mixture will curdle).

Chocolate Ganache Filling:

To make the chocolate ganache, heat the whipping cream in a bowl over a pot of boiling water. Add the chocolate and stir until completely mixed and glossy.

Place the bowl on the stovetop on medium heat and bring the mixture to a boil. Stir continuously for 4-5 minutes. Remove from the heat and set aside to cool. Then refrigerate for at least 3 hours or overnight.

Whip the chilled chocolate mixture until light and fluffy. If it’s too thick you can mix in a few tablespoons of whipped cream. Add red sour pitted cherries.

Syrup:

For the syrup, melt the sugar in a heavy-bottom saucepan over low-medium heat. Stir constantly with a spoon until sugar reaches a golden-brown colour. Pour the boiled water over the caramelized sugar and bring to a boil. Add the rum extract and remove from heat. Set aside to cool.

Assembling the cake:

Place the cake onto your work surface. Let it cool and then cut the cake horizontally in three.

Using a sharp knife, carve the middle and sides of the cake to make it look like a book.

Moist the cake layers with sugar syrup.

Place the first layer on your cake board and using a spatula, cover the top with the chocolate ganache . Place the second layer on top and cover with the mascarpone cheese mixture (saving a few tablespoons). Place the third layer on top and ice the cake with a thin layer of mascarpone mixture, covering all holes and imperfections.

Decorating the cake:

To cover the sides of the cake, roll out fondant in a long strip, 21 inches in length & 5 inches in width. Cut the fondant strip in half lengthwise.

Take a fondant strip and start covering the right side of the cake (starting from the middle at the front of the cake and finishing in the middle at the back). Do the same with the second strip of fondant for the left side of the cake.

To make the pages, roll out fondant (12 x 8 inches) and cover the cake. Smooth the fondant and trim the edges if needed. The first layer will cover any imperfections. Brush the cake surface with sugar syrup. Roll out another sheet of fondant and place on top of the cake. If you want you can slightly lift all four corners of the top fondant sheet like I did.

Make some deep lines along the sides of the cake, to simulate the edges of the pages and using a brush sprinkle some cocoa powder.  It’s better if you use sugar syrup and using a small brush, draw some lines on the sides of the cake . Your cocoa powder will stick easier.

Roll thin strips of pink fondant, approximately ½ inch in width, to wrap all the way around the cake. This will be the book’s cover.

Make a braided cord of fondant that looks like a bookmark.

Attach fondant decorations by brushing the back of the decorations with sugar syrup.

To make the cross, follow the steps in the pictures. Use a small brush and sugar syrup to ‘glue’ the parts together.