Coffee and Hazelnut Yule Log

Roast the hazelnuts in the oven for about 15 minutes at 150°C / 300°F. When they are lukewarm or cold, rub them between your hands to remove the skins (if a little remains, that’s fine).

In a heavy-bottomed saucepan or cast iron pot, bring the water and sugar to a boil. At 116°C / 241°F, remove from heat, pour the hazelnuts into the liquid sugar and stir to coat them with the sugar.

Return to medium heat and stir until the sugar liquefies again and caramelizes (this takes about fifteen minutes). You must not stop stirring to prevent the mixture from burning.

At the end of cooking, the hazelnuts should be glossy and a beautiful auburn colour. Spread them on parchment paper and leave to cool.

Once everything is completely cold, break up the nut brittle and place it in a food processor with the fleur de sel.

Rehydrate the gelatine in the water.

In a saucepan, heat the sugar, glucose and 80g (2.8 oz) of water to 103°C / 217°F.

In a pitcher, place the milk chocolate, rehydrated gelatin and unsweetened condensed milk, then pour the hot mixture over. Allow the chocolate to melt for a few moments then blend with an immersion blender.

Rehydrate the gelatine in the water.

Place the coffee beans on a baking sheet lined with parchment paper and toast them in a preheated oven at 150°C / 300°F for 10 minutes. Take this opportunity to also toast the coffee beans for the coffee mousse. Heat the cream and milk in a saucepan, then add the toasted coffee beans. Bring to the boil. Remove from the heat and leave to infuse for 10 to 15 minutes to fully flavour the mixture.

Strain the mixture to remove the coffee beans and return the infused cream to the saucepan. Add the instant coffee and stir to dissolve.

In a bowl, whisk the egg yolks with the brown sugar until you obtain a homogeneous mixture.

Pour the hot cream over the egg yolks while whisking vigorously to avoid cooking the eggs. Transfer everything to the saucepan and cook over medium heat, stirring continuously with a rubber spatula. Cook until the temperature reaches 83°C / 181°F.

Off the heat, add the rehydrated gelatine to the hot cream and stir until fully dissolved.

Immediately pour the hot cream over the milk chocolate in a jug. Leave to rest for one minute, then blend with an immersion blender to achieve a perfectly smooth cremeux. Add the pinch of fleur de sel and blend briefly once more.

Pour the cremeux into an insert mould, cover with cling film in direct contact with the surface, and freeze for 1 hour.

Melt the butter in a small saucepan, then leave to cool.

Preheat the oven to 200°C / 400°F.

In a bowl, mix the hazelnut powder, powdered sugar and eggs until you obtain a smooth batter.

In the bowl of a stand mixer, pour the egg whites and begin whipping at medium speed. When they start to foam, add the sugar in three additions while continuing to whisk. You are aiming for a glossy meringue with a bird’s beak peak.

Take one third of the whipped egg whites and fold them into the first mixture. Whisk quickly to loosen the batter. Then fold in the remaining two thirds in several additions, incorporating them gently.

Gently fold in the sifted flour, then add the cooled melted butter and mix one final time until the batter is smooth.

Pour the batter onto a baking tray lined with parchment paper and spread it with an offset spatula to an even thickness of about 5 mm. The goal is to obtain 2 rectangular sponge cakes.

Bake for 12 to 16 minutes, until the sponge is lightly golden. Leave to cool slightly, then slide the sponge onto a wire rack to stop the cooking and preserve its softness.

Then cut out 2 sponge cake rectangles (one will be slightly smaller than the base of your yule log mold and the other will match the dimensions of the insert).

Melt the milk chocolate in the microwave.

Add the hazelnut praline and mix well to incorporate it into the melted chocolate.

Add the crumbled dentelle crepes and mix carefully with a spatula.

Rehydrate the gelatine in water.

In a saucepan, heat the milk with the roughly crushed coffee beans and leave to infuse for 15 minutes.

In a bowl, whisk the egg yolks with the sugar.

Once the milk has infused, strain it, then add the instant coffee. Reheat, then pour over the egg/sugar mixture. Mix well and return everything to the heat.

Heat to 83°C / 181°F, stirring constantly. The cream will thicken. This is like cooking a crème anglaise — be careful not to exceed this temperature. If you don’t have a thermometer, you can test by running your finger across the back of a coated spatula: the line should remain clean.

Off the heat, add the rehydrated gelatine.

Whip the whole liquid cream, but do not over-whip — it should be light and mousse-like.

Pour three-quarters of the coffee mousse into the mould, spreading it well up the sides for a clean assembly. If the mousse is a little too liquid and to prevent the insert from sinking to the bottom, you can place the mould in the freezer for 5 to 10 minutes (keep an eye on it), just long enough for the mousse to firm up slightly. Remove the insert from the freezer and gently press it into the mousse, centring it carefully.

Add a thin layer of coffee mousse, leaving at least 1.5 cm (0.6 in) for the sponge.

Finish with the biscuit/crunch base (crunch side against the mousse). Press lightly to push it in and smooth the surface with a spatula.

Remove the entremet from the freezer and unmold.

Then place the frozen entremet on a rack, with the rack placed on a plate or dish to catch the excess.

Heat the mirror glaze to about 32°C / 90°F, blend it once more with an immersion blender being careful not to incorporate bubbles, and pour it delicately to cover the entremet entirely.

Remove the entremet from the rack and place it on a serving dish.

Arrange a few hazelnut skins on top (I also added small chocolate coffee beans).