Prepare the dacquoise biscuit: Preheat the oven to 340°F (170°C). Beat the egg whites until stiff peaks form, then gradually add the sugar. Gently fold in the cornstarch and almond flour. Spread the mixture onto a baking sheet and bake for 20 minutes.

Prepare the Bavarian cream: Start by making the caramel. Soak one sheet of gelatin in cold water. In a saucepan, combine the sugar and 2 tablespoons (30 grams) of water and cook until it turns golden brown. Heat the heavy cream and add it off the heat, stirring well. Add the salted butter and mix thoroughly. Once the caramel is lukewarm, add the gelatin sheet. Let cool.

Continue the Bavarian cream: Heat the milk. Whisk the egg yolks with the sugar until pale and creamy. Gradually add the milk, then return to the heat and cook until it thickens into a custard. Soften the remaining gelatin sheets. Add the caramel to the custard, then add the gelatin sheets. Let cool. Whip the heavy cream to soft peaks and fold it into the mixture. Refrigerate.

Prepare the lemon curd (inspired by Pierre Hermé): Soften one sheet of gelatin. Mix the lemon zest with the sugar. Add the eggs and mix. Add the lemon juice and mix again. Cook over a double boiler, stirring constantly, until the mixture reaches 180°F (82°C) and thickens. Remove from heat and let cool to 140°F (60°C). Add the butter and mix well. Add the gelatin sheet and refrigerate.

Peel and dice the apple. In a skillet, melt a small amount of butter with a little sugar and lightly caramelize the apple cubes.

Assemble the yule log: Place a round of dacquoise biscuit, then a layer of Bavarian cream. Add the lemon curd, then place some caramelized apples in the center. Finish with another layer of Bavarian cream. Pipe a little extra Bavarian cream in the center of your yule log. Freeze for 24 hours. Remove from the freezer 10 minutes before serving to add your desired finishing touches.