Tiramisu charlotte

Sift the flour and baking powder.

Beat the room temperature egg whites with a pinch of cream of tartar; add a quarter of the sugar, run on high to combine, then lower the speed and let it run.

Set the mixer to high and add the remaining sugar gradually to a firm-peak meringue.

Add the egg yolks to the meringue and mix until just combined, then fold in the sifted powders with a spider skimmer so the starch incorporates faster and the mixture does not deflate.

With a large plain tip, pipe two rows of 11 fingers, three inches (7.5 cm) long and one inch (2.5 cm) apart; fill the remaining batter into the prepared round pan.

Dust the ladyfingers with powdered sugar twice and bake at 375F / 190C for about 18 minutes, faster in a fan oven, until golden brown; they should be dry rather than soft.

Bake the chocolate crust pastry sandwiched between two baking mats and trays for 15 minutes.

Cut the round sponge in half and trim it to fit the cake ring.

Whip the mascarpone and heavy cream together to soft peaks.

For the pate a 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.

Incorporate the melted gelatin, then fold the pate a bombe into the mascarpone mixture.

Line a cake ring with acetate, set the chocolate crust on a tray or cake board, add the ring and spread about a cup of the filling; top with the first sponge and soak it well with coffee punch.

Add a thick layer of filling, the second sponge soaked with coffee punch, and finish with the remaining filling.

Freeze a couple of hours, then refrigerate overnight to set.

Trim the ladyfingers to the height of the cake, remove the ring and acetate, dust with cocoa powder, set the ladyfingers around, lightly moistened with the remaining coffee punch, and refrigerate.

For chocolate shavings, melt milk chocolate to 113F / 45C, cool in the refrigerator stirring now and then to 78F / 26C, re-warm quickly to 84F / 29C, mould and let set completely, then shave.