Lazio — abbacchio is specifically the Roman term for milk-fed lamb and the preparation is the emblem of the Roman Easter table. The term 'abbacchio' (from ad baculum — 'to the stick', referring to the shepherd's crook at the time of weaning) is Roman dialect. The recipe is documented in Roman sources from the 19th century.
Abbacchio is the milk-fed lamb specific to Lazio — an animal of no more than 30 days old, still on the ewe's milk, with pale, almost white flesh and extraordinary delicacy. The Roman preparation (alla cacciatora — hunter style) braises the abbacchio with white wine, anchovy (the umami foundation), rosemary, garlic, and white wine vinegar in a preparation that is simultaneously delicate and assertive. The anchovy dissolves into the braising liquid and provides depth without fishiness — a Roman technique of invisible umami elevation. The lamb, so tender it barely needs cooking, braises for 45 minutes and is served with the reduced pan juices.
Abbacchio alla cacciatora at the table has a sauce of extraordinary complexity for such simple ingredients — the anchovy has dissolved entirely but its umami depth permeates every molecule; the vinegar provides a subtle acidity; the rosemary is assertively aromatic. The lamb itself is pale, tender, and delicate against this flavourful backdrop. With Roman bread and a glass of Frascati, it is the taste of the Roman spring table.
Cut abbacchio into small pieces on the bone. Brown in olive oil over high heat in batches — deep colour on the outside of the milk-fed lamb is essential (the pale meat benefits most dramatically from browning). Remove; cook garlic and rosemary in the same oil until fragrant. Add anchovies (3-4 fillets per kg of lamb); stir until dissolved. Add white wine; reduce. Return lamb; add a splash of white wine vinegar; braise covered 30-40 minutes until tender. The sauce should be concentrated, fragrant, and anchovy-enriched. Serve immediately.
Abbacchio (milk-fed lamb, maximum 30 days) is available from specialist butchers in London, particularly in the Italian and Middle Eastern communities, in late winter-spring. Regular spring lamb can be used but the delicacy of the milk-fed animal is different. The white wine vinegar at the end of cooking is the acidity that cuts through the lamb fat and anchovy richness.
Not browning the lamb well — milk-fed lamb is pale; deep browning is what gives the dish its backbone. Over-braising — abbacchio is very tender; 45 minutes maximum; further cooking produces a mushy texture. Omitting the anchovy — the anchovy is the preparation's invisible depth agent; omitting it produces a pleasant but shallow result.
Anna Gosetti della Salda, Le Ricette Regionali Italiane; Giorgio Locatelli, Made in Italy