Pressure-cooker dulce de leche
Interest in pressure cookers may be on the rise in large part because of their modernist applications, but in some parts of the world it’s never waned: cooks from Morocco to Mexico have long relied on them as a labour-saving device for preparing traditional dishes in a fraction of the traditional time.
What makes pressure cookers so time-saving is that they allow you to speed up chemical reactions. Reaction rates increase with temperature, but at atmospheric pressure, the temperature of many foods won’t rise above 100°C, because that’s when all the water in them starts turning into steam. In a pressure cooker at 15 psi, the boiling point of water is as high as 120°C, which significantly speeds up reactions – in this case, the caramelization reactions in the condensed milk – giving you dulce de leche in 30 minutes rather than 3 hours.
Only… don’t expect that the faster cooking time is going to let you satisfy your cravings for dulce de leche instantly. You still have to let the pressure cooker cool down, and then let the can of newly made dulce de leche cool down, too, before you can dig in. What the pressure cooker really helps with in this case is the supervised cooking time. You wouldn’t want to leave an open pan of boiling water unattended for 3 hours, but you can leave a pot to cool while you go about other tasks.