Dark and White Chocolate Panna Cotta

Gelatine sheets first, because what you do with them prevents the one real failure in this dish: grainy or lumpy set. Soaking in cold water for ten minutes isn't fussiness — it lets the sheets hydrate evenly so that when you squeeze them out and drop them into hot (not boiling) liquid, they dissolve smoothly instead of leaving little rubbery threads. If you only have powdered gelatine, the rule is the same logic, different form: bloom it in a few spoons of cold water first, then melt it into the hot cream off the heat. Never add it straight to boiling liquid — gelatine's setting power breaks down above a certain heat, so "almost boiling" isn't a texture instruction, it's a protection for the gelatine itself.

Whipping cream carries the fat that makes panna cotta feel like panna cotta rather than a flavoured jelly — somewhere around 35–40% fat is what you want on the tub, because lower-fat cream sets thinner and tastes thinner too. The milk cuts that richness so the dessert doesn't sit like a brick after a Sunday roast; it's not there for any structural reason, just balance. If you've only got single cream in the fridge, don't substitute it for the double — it hasn't got the fat to carry the set, and you'll end up with something closer to a milk pudding.

Dark chocolate, finely chopped, melts from residual heat in the cream rather than direct heat — that's the whole reason it's chopped fine and not left in chunks: more surface area means it's fully melted before the cream cools below the point where it'll dissolve easily. Use a chocolate you'd eat on its own; 60–70% cocoa solids is a reasonable range — much higher and the bitterness fights the cream, much lower and you're really just adding sugar. White chocolate works by the same mechanism but behaves differently in the pan: it's mostly cocoa butter and sugar with no cocoa solids to speak of, so it melts faster and scorches more easily, which is exactly why that layer gets poured over it rather than simmered with it at all.

The vanilla pod in the white layer is doing a job the dark layer doesn't need — white chocolate is a quieter, sweeter flavour with nothing to push against it, so the vanilla gives it a backbone. Scraping the seeds rather than just dropping the whole pod in means you get the flavour distributed through the cream, not just steeped in one spot. No pod in the cupboard — a good vanilla extract, added once the cream's off the heat so it doesn't cook off, covers the same ground.

The two different chilling windows — four hours, then three more — aren't arbitrary. The first is a genuine wait: the dark layer needs to be firm enough on the surface to carry the white one without the two melting into each other, and in a domestic fridge, running colder and slower than any blast chiller, that's a real four hours, not an optional one. The second stage is shorter because the white layer is thinner and setting on top of something already cold, which gives it a head start. Patience is the one ingredient this recipe can't survive without — not flour, not timing to the minute, just leaving it alone in the fridge and finding something else to do with your afternoon.

Some say panna cotta needs to be turned out of a mould to count as proper panna cotta — no, because that tradition comes from restaurants wanting a sculptural plate, not from the dessert itself. Set in a glass and eaten with a spoon, it's the same dish, arguably an easier one for a kitchen that doesn't have matching moulds lying around, and nobody's Sunday is worse for it.