Twenty-eight layer chocolate cake

Cream the butter with the sugar in two batches, warming the bowl by hand if the kitchen is cold.

Beat in the room temperature eggs one at a time so the mixture does not go chunky.

Whisk the cocoa powder, cake flour, salt, baking soda and baking powder together.

Combine the coffee, milk and vanilla extract as the liquid.

Add the dry and wet mixtures to the creamed butter alternately, roughly one third at a time.

Divide the batter evenly between three parchment-lined eleven inch springform pans to the same height.

Bake at 325F for about 50 minutes to an hour; the low temperature keeps them flat and even.

Whisk the three whole eggs and five yolks together until homogenous.

Bring the whole milk and heavy cream to a scald, until wisps of steam rise from the surface.

Ladle a cup of the hot dairy into the eggs while whisking continuously, about three ladlefuls, to temper them.

Return the tempered eggs to the pot and bring back to a slow simmer.

Whisk in the flour and sugar mixture, then the cornstarch and cold milk slurry, stirring continuously.

Once it has thickened, take it off the heat and stir in the bittersweet chocolate and the vanilla extract.

Loosen with an extra cup of milk and an extra cup of cream, and add a quarter cup more sugar to taste.

Strain the custard through a fine mesh sieve, whisking, until silky and smooth; wrap and refrigerate until needed.

Cool the cakes completely, resting them a whole day, before cutting.

Level the cakes from the bottom by stacking them on something on a sheet tray and running the knife along the tray edge as a guide; aim for about half a centimetre per layer.

Slide a cake board under each thin layer to lift it off; patch holes with the dense cake itself.

Crumble the trimmings evenly onto a parchment-lined sheet tray.

Dry the crumbs in the oven at 350F convection for about 30 minutes, tossing occasionally.

Line the side of each springform pan with a strip of cake acetate.

Alternate a cake layer and a spread of chocolate custard, levelling each one, until the cake and custard run out; fourteen of each here.

Chill the assembled stacks in the freezer.

Cool the crumbs for about 30 minutes to room temperature, then blitz them fine in a food processor.

Pour the scalded cream over the chocolate, shake out air bubbles and cover with a cake board to let it warm through; if it does not come together, hold the bowl over a low flame and stir until glossy.

Pour the ganache over the stack that will be on top, tilt to spread it evenly, and tap the pan to release air bubbles.

Freeze both stacks overnight.

Spread leftover custard on the bottom stack as glue, unclip the springforms, peel the acetate and set the ganache-topped stack on top, aligned and level.

Fill the remaining holes on the outside with custard, then coat the edge with the cake crumbs, warming the custard with a blowtorch if it has frozen too hard to stick.

Let the cake stand an hour or two to come up to room temperature before slicing.

Cut with a knife dipped in hot water, or heated with a blowtorch, so it goes through the layers.