Casatiello is the great savoury bread of Neapolitan Easter—a ring-shaped enriched dough studded with cubes of salame, cicoli (pork cracklings), provola or pecorino cheese, and crowned with whole eggs nestled in their shells and held in place by strips of dough formed into crosses. The bread's appearance is as symbolic as its flavour: the ring shape represents the cyclical nature of life and renewal, the eggs symbolize resurrection, and the dough crosses echo the crucifixion. Casatiello is distinguished from its close relative tortano by the visible eggs on top (tortano has eggs hidden inside the dough, without the exterior decoration). The dough is a lard-enriched bread dough—flour, water, lard (strutto), salt, yeast, and cracked black pepper—kneaded until smooth and given a rise of several hours. The filling is generous: cubes of salame napoletano, cicoli (rendered pork fat scraps with meaty bits), and provola or sharp pecorino, distributed throughout the dough as it's rolled and shaped into a ring in a tube pan. The raw eggs in their shells are pressed into the surface and secured with crossed dough strips, then the whole construction rises again before baking. The baked casatiello is a magnificent object—golden-brown, fragrant with pork fat and black pepper, the eggs hard-cooked in their shells from the oven's heat, the interior revealing a swirl of salame, cheese, and cracklings embedded in soft, rich bread. It is traditionally made on Good Friday, left to cool overnight, and eaten on Easter Saturday and Sunday—at breakfast, for merenda (afternoon snack), or as part of the Easter picnic known as pasquetta. The leftovers, toasted in a pan, are among the great pleasures of the post-Easter week.
Use lard-enriched bread dough with black pepper. Fill with salame, cicoli, and provola/pecorino. Shape as a ring in tube pan. Crown with whole eggs secured by dough crosses. Two rises before baking. Make on Good Friday for Easter.
The lard should be strutto (rendered pork lard), not commercial vegetable shortening. Use a mix of cheeses for complexity—sharp pecorino and mild provola. The eggs can be removed after baking, peeled, and eaten alongside. Some families add a handful of grated Parmigiano to the dough for extra savouriness.
Using butter instead of lard (different flavour, wrong tradition). Skimping on the filling. Forgetting to secure the eggs properly (they fall during baking). Under-proofing the dough. Not letting it cool completely before cutting.
La Cucina Napoletana — Jeanne Carola Francesconi; Carol Field, The Italian Baker