Hazelnut-shaped dessert with hazelnut mousse, soft caramel, praline and sponge insert

Run toasted nuts in the processor until they turn into a paste.

Make a dry caramel without water, adding the sugar in two or three batches and stirring rarely, to a nice brown. Add the nuts and coat them; transfer to a silicone mat.

Once completely cool, cut the caramelized nuts into pieces and add them to the running food processor with fleur de sel to make hazelnut praline.

Bring milk to a boil, blend in toasted hazelnuts and infuse about 20 minutes. Pass, extracting as much liquid as possible.

Heat the infused milk with one third of the heavy cream until almost boiling; pour over white chocolate, add melted gelatin and blend, add hazelnut paste and blend, then the remaining cream. Chill overnight.

Heat heavy cream, corn syrup, vanilla and fleur de sel in one saucepan and keep it hot; in another make a caramel with sugar and corn syrup to a nice brown.

Pour in the hot cream slowly and cook the caramel to 105C.

Pass through a sieve, cool to 70C (160F), add the butter and blend.

Beat egg yolks with sugar until fluffy and creamy. Beat butter with hazelnut paste and combine the two mixtures.

Whip room temperature egg whites and sugar at high speed to a meringue; incorporate one third into the yolk mixture, then the rest.

Spread on a small baking tray and bake at 350F, 180C, for about 20 minutes.

For the insert, fill the first half of the cavity with hazelnut praline and the hazelnut biscuit, and freeze.

Whip the hazelnut ganache montee, without over-whipping.

Soften the room temperature soft caramel with some milk.

Fill each cavity of a 3D sphere silicone mold with hazelnut mousse and freeze 30 minutes. Dig out the center with a small ice cream scoop, fill with soft caramel and freeze 30 minutes; add the frozen praline and sponge insert.

Seal the lid and fill each sphere with the remaining mousse; freeze at least 6 hours until completely hard.

Unmold the spheres upside down onto a frozen baking tray so the caramel stays up; shave off the bottoms to stabilize. Pipe a dollop of mousse and curve it to mimic the nut; freeze and smooth with gloves.

Immerse each frozen cake in a 45C (113F) milk and cocoa butter coating glaze; once just set, brush the sides with a wire brush and dust with powder.

Wrap with a leaf of dark tempered chocolate and refrigerate overnight to thaw completely before serving.