Tiramisu yule log

Roll the chocolate crust into a 3 mm sheet, freeze about 30 minutes, and cut a rectangle a couple of millimetres larger than the mold, since it shrinks in baking. Freeze again until ready to bake.

Bake the crust sandwiched between two sheets of parchment or baking mats and trays to keep it flat, about 20 minutes.

Beat room-temperature egg whites with a pinch of cream of tartar; add a quarter of the sugar, lower the speed, then add the remaining sugar gradually to firm peaks.

Add the egg yolks to the meringue and mix until just combined.

Fold in the sifted powders with a spider skimmer so the starch incorporates faster without deflating the mixture.

Spread over lightly greased parchment on a baking tray and bake at 400F / 205C for about 12 minutes. Cool and freeze overnight, then unmold and cut to size, saving the leftovers.

Reduce espresso with a bit of sugar to a coffee extract; add more coffee and Kahlua or another spirit, then the agar agar mixture. Bring to a boil and cook a couple of minutes; cool over ice water and refrigerate.

Roll acetate into a 1 inch / 2.5 cm tube inside a cardboard tube and seal one end with tape.

Work the set gel to a smooth texture, fill the tube and freeze overnight; push the frozen cylinder out with a long wooden spoon. Alternatively freeze the gel in a half-moon silicone mold and demold.

Mix the mascarpone and heavy cream to soft peaks; it does not take long.

For the pâte à bombe, cook a sugar syrup to 250F / 120C and pour it by hand into the beaten egg yolks and eggs; beat on full speed until fluffy and cool.

Add melted gelatin, mix quickly, and incorporate the pâte à bombe into the mascarpone mixture, finishing with a whisk, to a mascarpone mousse.

Fill the yule log mold about halfway with filling and coat the sides with a spatula. Lay in the first sponge and soak generously with coffee punch, no dry spots.

Cover with more filling, tuck in the frozen coffee gel cylinder, add more filling, the last sponge, more coffee punch, and the chocolate crust. Freeze overnight.

For the optional glaze, pour hot cream with honey over bittersweet chocolate, let it sit a couple of minutes, and blend. (Cocoa dusting alone can replace the glaze.)

Demold the frozen cake and return it to the freezer. Bring the glaze to 40C and glaze the log; remove excess with acetate.

Transfer to a cake board, mark the glaze with a fork, dust with cocoa powder, and thaw in the refrigerator overnight.