Italian Salsa Tonnata (Piedmontese Tuna Sauce, Pellegrino Artusi 1891)

Method

1. 1Hard-boil the eggs (in parallel). Cover 2 eggs with cold water by 2 cm in a small saucepan, bring to a boil, then reduce to a gentle simmer for 10 minutes — fully hard-boiled, with a pale yellow yolk that crumbles dry, exactly what's needed for emulsion. Cool under running cold water for 2 minutes to stop the cooking. Peel and separate the yolks; reserve the whites for another use (egg salad, garnish). The yolks act as emulsifier and add body without the salmonella risk of raw yolks.
2. 2Drain the tuna. Open a 200 g can of quality Italian or Spanish tuna in olive oil — Ortiz Cantabrian, Callipo, Tonnino, or Maruzzella. Drain off most of the oil but reserve 1-2 tablespoons of the rich tuna oil for extra umami in the final sauce. Tip the drained tuna into the food processor bowl. Quality matters: do not substitute supermarket chunk light in water — the result will be flat and fibrous. The drained weight should be about 180 g.
3. 3Prep anchovies and capers. If using salt-packed anchovies (preferred — Cetara, Recca): rinse 4 fillets briefly under cold water for 30 seconds, then soak in cold water for 5 minutes to soften, lift out the central spine with a finger. If using oil-packed: pat dry with paper towel, no further prep. For capers: if salt-packed (Pantelleria), rinse 2 tablespoons under water for 30 seconds and soak for 10 minutes; if brined, drain and rinse briefly. Salt-packed give the deepest flavour but oil-packed and brined work well too.
4. 4Combine in food processor. Add the drained tuna, prepared anchovies, drained capers, the 2 hard-boiled egg yolks, 1 tablespoon of fresh lemon juice, and the reserved 1-2 tablespoons of tuna oil to a food processor or high-powered blender. Pulse 5-6 times for 2-3 seconds each to break everything down before continuous blending — this prevents motor strain and uneven texture.
5. 5Blend with olive oil drizzle. With the motor running on low speed, slowly drizzle in 100 ml of delicate extra virgin olive oil through the feed tube in a thin stream — like making mayonnaise. The slow drizzle is critical: dumping all the oil at once will not emulsify properly. Use a mild Ligurian or Spanish Arbequina, NOT peppery Sicilian or Tuscan — aggressive polyphenols oxidize during high-speed blending and turn the sauce bitter. Total blending time: 30-60 seconds maximum, until smooth and creamy.
6. 6Check texture and adjust. The finished sauce should be thick and creamy like mayonnaise, pourable but holding shape on a spoon. Too thick: add 1-2 tablespoons of cold water (or veal poaching liquid if making vitello tonnato) and pulse briefly. Too thin: add more drained tuna and pulse. Taste — salt is rarely needed (anchovies and capers provide salinity), but add a pinch if flat. A touch more lemon juice can brighten if too rich.
7. 7Rest in the fridge. Transfer to a glass jar or covered bowl and refrigerate for at least 1-2 hours before serving — flavours integrate, texture sets, the sauce thickens slightly. Best after 12-24 hours when 'aged taste' develops fully. Cover the surface with a thin film of olive oil to prevent oxidation if storing more than a day.
8. 8Serve chilled. Present salsa tonnata cold, never at room temperature — chill defines the proper silky texture. Spoon over thinly-sliced cold roasted veal for classic vitello tonnato; over halved hard-boiled eggs for egg tonnato; over thick tomato slices for tomato tonnato; over blanched asparagus or roasted vegetables; spread on focaccia or crostini; in tramezzini sandwiches with lettuce. Garnish with extra capers and chopped parsley. Pair with white wine — Arneis, Gavi di Gavi, Vermentino, or Pinot Grigio.