Curing egg yolks

About a week in the fridge for the initial cure, after which the yolks feel firm through the salt-sugar mixture rather than squishy. If you want them harder and more easily gradable, dry them further for a few days wrapped in cheesecloth in the fridge, or briefly in a very low oven. Cooler, longer curing gives a firmer result. So the basic version is ready in five to seven days, with optional extra drying for a denser texture.

The salt cure preserves the yolks by drawing out moisture and creating an environment hostile to spoilage, similar in principle to cured fish like gravlax, and they are typically eaten grated or sliced without further cooking. That said, use very fresh, good-quality eggs, keep everything clean and refrigerated throughout, and if you have any concerns about raw-egg safety for vulnerable people, take that into account. Properly cured and refrigerated, they keep for several weeks.

A broken yolk usually means the egg was not fresh enough or was handled roughly, since fresh yolks have a stronger membrane that survives transfer. Roll them gently into their wells rather than dropping them. A yolk that stays soft was likely undercured, so give it more time, the salt needs long enough to draw the moisture out fully. Make sure each yolk is completely buried in the cure too, since exposed parts firm unevenly.

Grate or shave them over food as a rich, savoury finishing touch, much like you would use hard parmesan or cured fish roe. They are excellent over pasta, risotto, salads, roasted vegetables, avocado toast, or soups. The flavour is intensely umami and a little goes a long way, so a light grating adds a luxurious savoury depth. They are a finishing garnish rather than a main ingredient, prized for the concentrated hit they bring.