Altamiras’s recipe for crumb custard is laconically brief, but it offers nearly as many precise measurements as modern recipes: “Grate bread, toast it, and when it’s well browned take two bowls of milk, four ounces of sugar and two pairs of beaten eggs for every dish of custard.” Deliciously soothing, with soft or crunchy crumbs lending texture, the recipe has never received much attention from food historians. In medieval centuries it was called “Llet malcuita”, most famously in the Catalan manuscript Sent Sovi, in which it was made with almond or goat’s milk, but Altamiras probably used goat’s or cow’s milk, his breadcrumbs would have been wholegrain, and his cane sugar unrefined. Stale sponge-cake crumbs replace the bread in a 1780s friary recipe by Sever de Olot, who said his version was for “madres monjas y demás señoras” – mother superiors and other ladies – probably a reference to female cake baking. By comparison, Altamiras’s version wins for its rusticity, with big crunchy nuggets of toasted breadcrumbs in the custard and a lightly, naturally browned but not caramelised top crust. To recreate this effect, originally produced by baking dishes’ recessed lids filled with glowing embers, place your half-filled dish of custard ready to cook in a bain marie in the oven and, once safely in place, top up the custard to the brim. Today’s convent recipes still use breadcrumbs, they add cream and grated lemon zest to the milk, and the custard is often baked in a caramelised mould. As shown in the photos I like to infuse the milk with different spices and flavourings – for example with cinnamon, red peppers, star anise and orange zest – and to serve the custard with a liquid sauce and a creamy one. A dark, slightly bitter liquid caramel goes well with a small handful of roughly chopped, scattered toasted almonds, and separately, you can pass an eyecatching kéfir or crème fraîche tinted with puréed fresh or frozen forest fruits.