Bûche de noël au praliné

Preparing the Joconde sponge:

1. 1Preheat the oven to 180°C (fan-assisted).
2. 2In a large bowl, mix the whole eggs with the almond-sugar mixture.
3. 3Whisk until the mixture is foamy and slightly pale.
4. 4Sift the flour and gently fold it into the previous mixture using a spatula or whisk.
5. 5Whip the egg whites to stiff peaks with the pinch of salt.
6. 6Gradually add 30 g of sugar (if needed to stiffen the whites).
7. 7Gently fold the whipped egg whites into the main mixture in several additions, to avoid deflating it.
8. 8Gently add the clarified butter to the mixture, lifting the batter to keep it light.
9. 9Spread the batter evenly on a 33.5 x 33.5 cm baking sheet lined with parchment paper (or a silicone mat).
10. 10Make sure to get an even thickness of about 5 mm.
11. 11Bake for 10 to 12 minutes, or until the sponge is lightly golden but still soft to the touch.
12. 12Once out of the oven, let the sponge cool for 2 minutes, then gently unmold it onto a wire rack.

Preparing the praline buttercream:

1. 13Heat the sugar with 80 ml of water in a saucepan to get a syrup at 121°C.
2. 14Beat the egg yolks in a large bowl until foamy.
3. 15Pour the hot syrup in a thin stream over the yolks while continuing to whisk.
4. 16Whisk until the mixture cools down and becomes creamy.
5. 17Gradually add the softened butter while continuing to whisk until smooth and even.
6. 18Fold in the praline paste and mix gently until the cream is well flavored.
7. 19Keep refrigerated until use.

Preparing the soaking syrup:

1. 20Pour the water into a saucepan and add the granulated sugar.
2. 21Bring the mixture to a boil.
3. 22Stop cooking as soon as the sugar has completely dissolved.
4. 23Stir in the amber rum to your liking, adjusting the amount to taste.

Assembling the log:

1. 24Soak the Joconde sponge with the soaking syrup using a pastry brush.
2. 25Spread the praline buttercream over the Joconde sponge in a thick, even layer.
3. 26Roll the Joconde sponge onto itself to form a log (make sure the seam ends up underneath).
4. 27Cover the log with praline buttercream using a piping bag fitted with a basket-weave nozzle.
5. 28Decorate the log as desired, with chocolate shavings, meringues, fruit, etc.
6. 29Let the log rest in the refrigerator for at least 2 hours before serving.