I didn't grow up with bolo do caco. That's a Madeiran thing, and my roots are Alentejo. But the first time I tasted prego em bolo do caco in Funchal, standing at a kiosk near the Mercado dos Lavradores with grease running down my wrist, I understood why the Madeirans guard this recipe so fiercely.

The bread is everything. Bolo do caco isn't quite bread, isn't quite flatbread, isn't quite anything you've had before. Sweet potato in the dough gives it that slight sweetness, that tender crumb that tears instead of crumbles. Traditionally it's cooked on a caco, a flat basalt stone heated over wood fire. You can smell them cooking from streets away.

The prego itself is simple. Thin beef, pounded tender, marinated in garlic and wine and bay leaf. Seared hard and fast until the edges char but the center stays pink. Then it goes straight into the bolo do caco that's been split and slathered with garlic butter. The butter melts. The meat juices soak into the bread. You eat it standing up because sitting down would waste precious seconds.

At Mesa da Avó, I've served this as a late-night dish, after the main courses, when everyone's had wine and the formality has melted away. People fight over who gets to make the next one. This is what Portuguese street food is supposed to be: fast, satisfying, and absolutely non-negotiable in its simplicity.