Black Forest Yule Log

Ingredients

Method: Frozen Chocolate Crémeux

1. Place the cream and milk in a small saucepan over medium heat and bring it to a simmer. Meanwhile, in a heat-proof bowl, briefly whisk together the egg yolks and sugar. In a separate heat-proof bowl, place the chocolate.
2. Pour 1/3 of the hot milk-cream mixture over the eggs and whisk immediately until thoroughly combined. (This process is called tempering the eggs. It allows us to bring up the temperature of the eggs and prevent scrambling or cooking them too fast.)
3. Pour all of the egg mixture back into the saucepan and cook on a low-medium heat, whisking constantly. Keep doing so until the mixture has cooked and thickened. You now have a custard. You’ll know it’s ready when a thermometer inserted into the mix reads 83°C. Alternatively, you can draw a line through the custard using the back of a spoon. If the line holds its shape, then the custard has been cooked properly.
4. Pour the custard mix into a sieve that is placed over your bowl of chocolate. This will catch any lumps. Use a spatula and stir until the mixture is thoroughly combined.
5. Using a blender (ideally a stick blender), blend the custard and chocolate to create a silky smooth crémeux. Pour into a container and cover with cling film so that it is touching the surface of the custard. (This will prevent a dry layer of film from forming.) Place in the fridge for at least four hours, preferably overnight.
6. Once it has set, pipe the crémeux in a straight line on a plate, baking tray, or parchment to create the centre of our yule log. Freeze for at least 1 hour, until frozen through.

Method: White Chocolate Chantilly Cream

1. Divide the double cream in half (150g each) and keep one half chilled in the fridge.
2. Bloom the gelatine powder by mixing it with the 12g of cold water and allowing it to stand at room temperature for 10 minutes, then move to the fridge for a further 10 minutes. Meanwhile, place chopped white chocolate in a bowl and set aside.
3. In a small saucepan over medium heat, bring the non-chilled half of the cream and vanilla paste to a simmer. Add the bloomed gelatine mass and stir until it melts. Pour over the chocolate and allow it to stand for 1-2 minutes. Use a spatula and stir until the mixture is thoroughly combined. Pour the remaining chilled double cream into the mix and stir again until combined.
4. Pour the contents of the saucepan into a container and cover with cling film that is touching the surface. Chill in the fridge for at least 4 hours, preferably overnight.

Left: Crémeux before being piped and frozen. Right: Chantilly cream being spread on sponge cake before being rolled. 

Method: Dark Chocolate Ganache

1. Place the double cream in a small saucepan over medium heat and bring it to a simmer. Meanwhile, place the chopped chocolate in a heat-proof bowl.
2. Once the cream is hot, add it to the chocolate and let it stand for 1-2 minutes before stirring with a spatula until combined.
3. Blend (ideally with a stick blender) for a silky-smooth finish, and pour into a container with cling film touching the surface. Leave at room temperature for at least 4 hours, preferably overnight.

Method: Rolled Choux Sponge Cake

1. Preheat oven to 160°C fan. Bring 70ml whole milk, 50g unsalted butter, and 25g caster sugar to a boil in a large saucepan.
2. In a separate bowl, mix the 50g plain flour and 15g cocoa powder together and add to the boiling milk all at once. Over heat, use a spatula to bring the dough together for 1 minute, until the mixture comes off the edges of the pan and clumps together. 
3. Empty the contents of the saucepan into the clear bowl of the Ankarsrum Stand Mixer fixed with the cookie whisks. Mix on a low speed. Once the choux is cool to the touch, slowly add in 50g egg (about 1 medium egg) and 85g egg yolks (from 3-4 medium eggs) until combined and shiny. Increase the speed and allow it to beat for a further 1-2 minutes. Place this mixture in a separate bowl, and clean out the clear bowl of the Ankarsrum to make the meringue.
4. Return the cleaned clear bowl to the Ankarsrum mixer and attach the balloon whisks. Add 125g egg whites (from 3-4 eggs) and whisk on medium speed until frothy. Continue on a medium speed and gradually add in 130g caster sugar. Once all the sugar is added, increase the speed to high and stop when the meringue can form high peaks that hold their shape.
5. Carefully fold the meringue into the rest of the batter in the separate bowl. Be gentle as we do not want to knock out too much air at this stage. Pour the batter on a rimmed baking tray lined with a silicone mat and level it flat with an offset, angled spatula. Bake for 8-12 minutes. Your sponge cake is done when a skewer inserted in the middle comes out clean. The cake should feel flexible enough to roll over itself.
6. Remove the cake with the silicone sheet under it and allow it to cool completely off heat, so it does not overcook.

Method: Assembly

1. Using the clear bowl of the Ankarsrum Stand Mixer, whisk the chilled Vanilla White Chocolate Chantilly Cream until it can form soft peaks that hold their shape. Chop the maraschino cherries and set aside, along with some syrup from the jar.
2. Carefully remove sponge cake from the silicone mat and place on a large piece of parchment paper. Using a pastry brush, brush the cherry syrup over the entire surface of the sponge cake. Using an offset angled spatula, spread the Chantilly cream evenly across the sponge. Scatter the chopped maraschino cherries over the cream-topped sponge cake.
3. Roll the short edge of the sponge cake over itself into a log, ensuring the roll is tight. (You can use the parchment paper to lift the sponge cake and aid in this.) Once shaped into a log, place the cake in the freezer for 30 minutes just to firm up the roll, making it easier to handle.
4. Remove from the freezer and cut the ends off the log to expose the roll design on the inside. Cover the yule log with the room-temperature dark chocolate ganache and use a small offset spatula to create a tree bark effect. Dust with cocoa powder and serve.

BK Tips

• This Rolled Choux Sponge Cake makes an excellent base for any Swiss roll recipe. 
  
  
• Feel free to use the stainless steel bowl of the Ankarsrum stand mixer attached with the dough roller for mixing the choux batter, and the clear bowl for the French meringue. (Just make sure the batter is thoroughly combined and shiny before setting it aside.) Then you can fold the meringue directly into the stainless steel bowl containing the rest of the batter with a spatula.
  
  
• You can make this cake up to two days in advance, storing it in an airtight container in the fridge. If dusting with cocoa powder, do it just before serving.