Dark chocolate log with vanilla insert

The preparation step by step

1. Moisturizes and prepares vanilla cream

   Pour 2 g of gelatin over 12 g of cold water. Whisk the yolk, 25 g of sugar and 10 g of starch in a bowl. Heat the 150 g of milk with the vanilla, pour half over the egg mixture by whisking and then reverse in the saucepan.

2. Bake and mold the vanilla insert

   Make it thick by whisking over medium heat. From the first boil, cook for 1 minute. Out of heat, incorporate the hydrated gelatin and then pour into a 22 x 3 cm insert mold (about 200 ml). Let cool for 20 minutes then freeze for at least 4 hours.

3. Prepare the base of dacquoise

   Preheat the oven to 170 °C in conventional oven setting (no fan). Draw a 28 × 14 cm rectangle on the reverse of a sheet of baking paper and place it on a baking tray. Sift the 40 g icing sugar and 10 g flour, then mix with the 50 g ground almonds.

4. Whisk the egg whites, then fold in to loosen the mixture

   Pour the 80 g egg whites into a clean mixing bowl. Whisk on medium speed. When they become frothy, add the 40 g of sugar in three additions. Stop when a soft peak holds at the tip of the whisk. Fold in the dry ingredients with a spatula, lifting the mixture from the bottom over the top.

5. Cuis la Dacquoise

   Spread the batter within the 28 × 14 cm rectangle without pressing out the air. Bake for 16 to 18 minutes, until the top is pale golden and flexible and the edges release easily. Allow to cool for 30 minutes before removing the paper. A base that is still warm would melt the mousse.

6. Adjusts the sole to the mold

   Cut a strip of 24 x 8 cm, or 5 mm smaller than the opening of the mold on each side. Set the offcuts aside to serve as a snack. Do not stack and compress several layers inside the log: keep the base thin.

7. Chop the chocolate

   Finely chop the 200 g of dark chocolate and place them in a dry bowl. Heat the 120 g of cream in a saucepan until the first frizz. Turn off the heat immediately.

8. Emulsify the ganache

   Pour a third of the hot cream over the chocolate. Stir in the centre with a spatula until a glossy core forms. Add the other two thirds one after the other while continuing to mix. Avoid whisking, so that no air bubbles are incorporated.

9. Mature the ganache

   Add the 230 g of cold cream, mix, then press cling film directly onto the surface. Refrigerate for 8 hours. The mixture must be cold all the way through before whisking; half an hour in the refrigerator is not enough.

10. Whip the cold ganache

    Pour the ganache into a refrigerated bowl. Whisk on medium speed for 1 to 3 minutes, watching continuously. Stop as soon as the whisk leaves trails and the mixture holds on the whisk. Overwhipped ganache becomes grainy; use it as soon as it is softly whipped.

11. Fill the mold without bubbles

    Place the mold on a rigid board. Use a spoon to spread about half the mousse over the base and up the sides of the mould. Tap the mould gently to release large air pockets. Unmould the frozen insert and place it in the centre, pressing gently without letting it touch the bottom. Cover with the remaining mousse, leaving about 1 cm for the biscuit base. Pour any excess into a small serving glass and refrigerate.

12. Close with biscuit

    Place the cooled biscuit base on the mousse. Press lightly to level the base without pushing it into the mousse. Smooth the edges, cover and freeze for at least 8 hours, keeping the mould level.

13. Unmould the frozen log

    The next day, put a serving dish in front of you. Gently remove the mould from the completely frozen log, without pulling on the mousse. Remove any cling film and place the log biscuit-side down on the serving plate. A log that has only been refrigerated would be too fragile to unmould this way.

14. Let thaw in the cool

    Refrigerate the demoulded log for at least 6 hours at 4 °C maximum before serving. Thaw in the refrigerator, not on the work surface. The centre should yield to the knife: if it is still hard, allow more time to thaw in the refrigerator.

15. Add the shavings

    Draw a vegetable peeler along the edge of the dark chocolate bar to make 20 g shavings. Simply distribute them in the center of the cold log, without covering the entire surface.

16. Serve regular shares

    Dip the knife blade in hot water, wipe it thoroughly, then slice without crushing the cake. Wipe the blade between slices to keep the layers clearly defined. Take out only the amount you plan to serve and return the rest of the log to the refrigerator.