Caramel custard cake

Preheat the oven to 350F with a water bath heating inside, about half an inch of water, as high as the custard layer; heat the cake pan in the oven too.

Make a dry caramel: heat sugar until melted and amber, dark for a slightly bitter flavour or lighter if preferred; stir only to even out dark spots and watch it, as it burns fast.

Pour the caramel quickly into the hot cake pan and swirl to coat; pop any large bubbles.

For the custard, beat four egg yolks with sugar immediately so the sugar does not cook the yolks; add evaporated milk and a little vanilla, stir until the sugar dissolves, and set aside without pouring it in yet.

For the cake, combine cake flour, baking powder and salt, and sift.

Zest an orange with a microplane, avoiding the bitter white pith, then juice it.

Mix two egg yolks with sugar, then three tablespoons of vegetable oil, the orange juice and a touch of vanilla.

Pour the wet into the dry and whisk until there are no lumps; cake flour's low protein means little risk of developing gluten.

Whip three egg whites with a little cream of tartar until foamy, then drizzle in sugar a little at a time and beat to stiff peaks without over-beating.

Stir about a third of the meringue into the base to lighten it, then fold in the rest in two batches, turning the bowl, until no streaks of white remain.

Strain the custard through a small sieve over the caramel in the pan, then gently pour the batter over it; it floats on the denser custard. Run a toothpick through any large bubbles.

Bake in the water bath 45 to 50 minutes, judged by time and a golden-brown top, since a tester cannot show the custard's doneness.

Flip immediately out of the oven, before the chiffon shrinks: run a spatula round the sides, set a plate on top and invert, jiggling to release.

Cool and chill in the fridge for a few hours before cutting.