Hazelnut and coffee are a great combination, and this torte has it all: crunchy hazelnuts, crispy hazelnut meringue, and a luscious coffee-flavored buttercream. For this cake I used the recipe of the famous retired Dutch pastry chef, Cees Holtkamp. I’ve posted a hazelnut meringue cake with a simplified buttercream before, and CampariGirl commented that I should try to make the real thing. To make buttercream, you first need to make pastry cream. This cake is a lot of work, but it is worth it!
For a 24 cm (9″) torte
2 egg whites
pinch of salt
110 grams (9 Tbsp) sugar
85 grams (1/3 cup) confectioners’ sugar
190 grams (1 1/3 cup) hazelnuts
For the buttercream
100 grams (1/2 cup) sugar
150 grams unsalted butter, soft
250 ml (1 cup) whole milk
1/2 vanilla bean
25 grams (2 Tbsp) flour
2 egg yolks
To flavor the buttercream
1 Tbsp espresso or very strong coffee
1 tsp brown sugar
1 tsp instant espresso powder
Add the teaspoon of brown sugar to the espresso.
Add the instant espresso powder.
Stir and allow to cool.
Toast the hazelnuts for 10 minutes at 160ºC/320ºF.
Put most of the milk in a saucepan, reserving a couple of tablespoons. Add the vanilla bean, cut in half lengthwise, and bring to a boil.
Put the flour with the egg yolks in a bowl. Add the reserved cold milk.
Whisk until the mixture is smooth.
When the milk boils, turn off the heat.
Add the hot milk to the egg yolk mixture in a thin stream…
Return the mixture to the saucepan.
Cook, stirring, over medium heat until the pastry cream thickens. Turn off the heat.
Add 50 grams (1/4 cup) of sugar, and stir until the sugar has melted.
Cover with plastic wrap such that the foil touches the surface of the pastry cream. This will prevent the formation of a skin.
Put the egg whites in the bowl of a stand mixer with a pinch of salt. Use the balloon whisk to beat the egg whites until soft peaks form.
Add 110 grams of sugar while the motor runs.
Keep the motor running until the egg whites show stiff peaks when you lift the whisk.
Combine the confectioners’ sugar with 75 grams of the hazelnuts in a food processor.
Grind to obtain a fine powder. Keep 2 tablespoons of this mixture separate.
Add the hazelnut powder to the meringue.
Gently fold the hazelnut powder into the meringue, working from the bottom.
Line two baking sheets with parchment paper. On each baking sheet, create a 24 cm (9″) circle of the hazelnut meringue.
It helps to use springform pans…
…to make nice circles.
Bake the meringue circles at 120ºC/250ºF (fan forced) for 45 minutes.
Allow the meringue circles to cool.
Combine the pastry cream, the remaining 50 grams sugar, the reserved 2 tablespoons of the ground hazelnut mixture, and the coffee mixture in the bowl of the stand mixer.
Whisk to mix.
Add the butter in cubes.
Whisk to mix.
Holtkamp advises to use a blowdrier to warm up the bowl to make it easier to whip the butter in the cream. Since I don’t have a blowdrier, I resorted to using an immersion blender instead.
The object is to get a smooth mocha-flavored buttercream.
Transfer the cream to a piping bag.
Take one of the two circles of hazelnut meringue.
Put a layer of buttercream on top.
Flatten the buttercream with a spatula.
Arrange the other circle of hazelnut meringue on top.
Cover the top and sides with buttercream.
Reserve some hazelnuts for decorating the top, and roughly chop the rest.
Decorate the top with hazelnuts and the sides with the chopped hazelnuts.
Store in the refrigerator. This torte is best the next day.
Although flaking is a bit of an issue for serving, cod sous-vide has a great texture.