Jamoncillo

Jamoncillo belongs to Mexico's long colonial tradition of cooked-milk sweets — dulces de leche made by reducing milk and sugar — that grew up after the Spanish introduced cattle, sugarcane and the convent confectionery of New Spain, where nuns and home cooks turned abundant milk and sugar into candies. The sweet is widespread, with strong associations to the dairy-and-pecan country of the north and the Bajío; pecan-studded jamoncillo is especially tied to states such as Nuevo León, Coahuila and San Luis Potosí. As a folk confection it carries no single inventor or origin date. The name is usually explained by the candy's resemblance to a small ham or a firm bar; the same sweet is known regionally by other names, and is kin to the broader family of dulce de leche and cajeta.

Jamoncillo is firm but yielding — it gives under the teeth and turns smooth and almost melting, fudge-like rather than chewy or hard. The flavor is pure cooked milk: sweet, mildly caramelized, with the soft dairy depth of milk reduced low and a warmth of vanilla or cinnamon. Done right it is fine-grained and creamy on the tongue, never sandy. Where pecans are folded in, their toasty, buttery crunch breaks the smoothness; the pink-and-white layered kind tastes much the same, the color mostly for show. It is rich and quite sweet, meant for a small square at a time.

Jamoncillo is a crystallized milk fudge, and the craft is the opposite of caramel-making. Milk and sugar are simmered down, often with a little baking soda to help the milk brown and stay tender, until the mixture thickens and a candy thermometer reads the soft-ball stage (around 112–116°C), where enough water has cooked off for the sweet to set firm. It is then taken off the heat and beaten as it cools — and that beating is the whole point: agitating the cooling syrup forces the dissolved sugar to crystallize into a multitude of tiny crystals rather than a few large ones, which is what gives fudge its smooth, opaque, sliceable body instead of the clear, glassy hardness of an uncrystallized caramel. Beating too early (while too hot) or too late both coarsen the grain. The thickened candy is then pressed into a tray or shaped, the pecans folded in before it sets, and cut once firm. Reducing the milk also concentrates and gently caramelizes its sugars and proteins, deepening the cooked-milk flavor.