Sharlotka

Heat the oven to 180C/350F.

Butter a 22cm springform tin heavily with the softened butter and line the base with parchment.

Toss the apple pieces with the lemon juice and 1 tsp of the cinnamon.

Cut the apples last, immediately before you start whisking. Cut apple begins to weep within about fifteen minutes, and that juice ends up as a sodden layer at the bottom of the cake.

Whisk the eggs and caster sugar at high speed for 6-8 minutes, until pale, roughly tripled in volume, and thick enough that a drizzle from the beaters sits on the surface for 3 seconds before sinking.

This is the only real leavening in the cake. Under-whisked, it bakes dense and slightly rubbery, and no amount of baking powder makes up for it.

Whisk in the vanilla.

Sift the flour, baking powder, the remaining 1 tsp of cinnamon and the salt over the foam in three additions.

Fold each addition in with a spatula, cutting down through the middle and turning the mixture over, and stop the moment the flour disappears.

The batter will look thick and there will not seem to be enough of it. That is right: at this ratio the batter coats the fruit rather than suspending it.

Tip off any juice the apples have released, then fold them in with about a dozen strokes.

Scrape into the tin, level the top and push down any apple pieces standing proud, which would scorch.

Bake for 45-55 minutes, until deep gold, springy in the centre, and a skewer comes out with no wet batter on it. Apple juice on the skewer is fine.

If the top is dark before the centre is set, lay a sheet of foil over it and carry on.

Cool in the tin for 30 minutes before releasing the ring, so the fruit-heavy crumb has time to firm.

Dust with the icing sugar and serve warm or at room temperature.

Eat it on the day it is baked. The fruit softens the crumb overnight and by the second day it is closer to a pudding.