Tiramisu icebox cake

Mix the brewed coffee and the Kahlua in a shallow bowl as the soak; the coffee should be room temperature.

Line the loaf pan with two criss-crossing pieces of plastic wrap, wetting the inside of the pan lightly first so the plastic sticks.

Put the egg yolks in a medium bowl.

Combine the granulated sugar, instant coffee, kosher salt, vanilla and water in a small saucepan.

Stir over heat until the sugar and coffee dissolve, then bring to a boil, a minute or two.

Beat the yolks on medium with the hand mixer and stream in the hot syrup slowly, which cooks and pasteurizes them; pouring too fast cooks the yolks.

Turn the speed up to medium high and beat until light, airy and mousse-like, thick enough to ribbon, and back to room temperature, a couple of minutes; feel the outside of the bowl to check.

In a large bowl combine the mascarpone with half a cup of the heavy cream and whip, starting on low or medium low, until firm peaks with no lumps. Keep the remaining cup of cream in the fridge.

Scrape the yolk mixture into the mascarpone mixture and beat again from low up to medium high to firm peaks, glossy, thick and very light; do not overwhip or it will go grainy like butter.

Trim the tiniest nub off the ladyfingers so a row sits in the narrower base of the loaf pan; between six and seven ladyfingers make one row.

Scrape half a cup of filling into the bottom of the pan and spread it into a thin layer with the back of a spoon or a small offset spatula.

Dip each ladyfinger in the soak for about one second with one quick turn, since they absorb liquid very fast, and arrange them in a tight row across the bottom.

Spread a cup of filling over the ladyfingers, then another layer of dipped ladyfingers, then another cup of filling, then a third and final layer of ladyfingers.

Scrape the remaining filling, about half a cup, over the final layer and smooth it to the edges.

Fold the plastic overhang up and over, pressing it directly onto the surface, and press it flat and smooth.

Chill in the fridge at least 12 hours, until the filling is set and sliceable and the ladyfingers are soft all the way through.

Whip the remaining cup of cold heavy cream, unsweetened, starting on medium low and increasing as it thickens, to medium peaks so it holds its shape.

Invert the cake onto a serving platter, pulling down on the plastic if needed to dislodge it, and peel the plastic away.

Spread the whipped cream over the top and down the sides, leaving it billowy rather than smooth.

Tap a little unsweetened cocoa powder over the top for a speckled finish, going light because the cocoa is strong and bitter.