First step: the pear insert.

1. Soften the gelatin sheets in a bowl of cold water for 10 minutes, and drain. In a saucepan, heat the pear puree, sugar, allspice (if using), and lemon juice. Add the drained gelatin to the saucepan off the heat. Mix well.
2. Pour the pear insert into the insert mold of your log mold and place in the freezer for 3 hours.

Second step: the dacquoise (biscuit).

1. Preheat the oven at 350°F (180°C).
2. Add the egg whites to the bowl of a food processor equipped with the whisk, and beat on medium speed. When the whites start to foam but are not firm yet, gradually pour the sugar while still beating. Keep beating until stiff peaks form. Gently stir in the confectioners’ sugar, flour and almond flour, using a rubber spatula.
3. Spread onto a baking sheet lined with parchment paper, making it slightly larger than the dimensions of the mold, and bake for 15-20 minutes.
4. Let cool slightly, then invert onto a cutting board and cut to the dimensions of your mold.

Third step: the biscoff base.

1. Place the biscoff spread with the milk chocolate in a bowl and melt in the microwave. Using a rolling pin or a small food processor, pulse the Gavottes until crumbled. Add them to the biscoff mixture, and stir.
2. Spread onto a baking sheet into a strip slightly larger than the yule mold. Place in the freezer for 30 minutes. Then, re-size to the exact size of the yule mold (using a ruler and a large sharp knife).

Fourth setp: the pear mousse.

1. Soften the gelatin sheets in a bowl of cold water for 10 minutes, and drain. In a saucepan, heat the pear puree, sugar and vanilla. Add the gelatin sheets to the saucepan off the heat. Mix and leave to cool at room temperature.
2. Once the pear puree has cooled, whip the very cold whipping cream into whipped cream, using a hand mixer. Gradually add the whipped cream to the pear puree and stir gently, until fully incorporated.

Assembing the bûche.

1. Pour about two thirds of the pear mousse into the log mold, making sure it covers the sides of the mold, and place in the freezer for 30 minutes.
2. Unmold the log insert and place it carefully into the pear mousse. Cover with the remaining pear mousse, add the biscoff strip and the dacquoise. Place the log in the freezer for at least 7 hours or ideally overnight.
3. Invert the Christmas log onto serving dish, and thaw in the refrigerator for 6 hours before serving. Decorate with crushed Speculoos.