14th Century Gourd Soup

A medieval potage stripped down to its bones: squash simmered in broth, thickened with egg yolk and fat, gilded with saffron. The whole dish hinges on the liaison at the end, which will scramble if the pot is boiling when it goes in.

• The gourdFourteenth-century "gourds" were most likely young bottle gourd (Lagenaria), picked small and tender so the skin pares off and the seeds are still soft. Young zucchini, pattypan or a small trimmed calabash from an Asian grocer all behave the same way. Winter squash is the wrong texture — it purees rather than holding its cut pieces.
• Cut and cooking timeInch pieces in simmering broth need 8 to 12 minutes, no more; taken past that point the flesh collapses and the soup turns cloudy.
• "A good broth"Meat stock, not water — a well-made chicken or beef broth. The recipe carries no salt of its own beyond the pork, so use unsalted or low-salt stock and season at the end.
• Ground salt pork with egg yolksThis is the thickener, a fat-and-yolk liaison rather than a garnish. Work finely minced or food-processed salt pork into the raw yolks, slacken with a ladle of hot broth, then stir the mixture into the pot off the heat or at a bare 170-180F. If it boils it will curdle and the pork will separate out in grains. Roughly 2 oz salt pork and 3 yolks per quart of broth.
• Salt porkCommercial salt pork can be very salty. Blanch it a minute or two in water first, taste the broth before adding any further salt, and expect not to need any.
• SaffronA large pinch, about 20 threads per quart, crumbled and steeped in a spoonful of hot broth for ten minutes before it goes in. Added dry to the pot it colors unevenly and much of it is wasted.
• AllspiceAllspice is a New World berry and cannot have been in the fourteenth-century original; it is the redactor's substitute. A pinch works, but a mixed powder douce of ginger, cinnamon and grains of paradise or long pepper is closer to what the period pot would have held.
• YieldAs written the quantities are entirely open. Treat it as a light first course: a quart of broth and about a pound of prepared gourd serves four.