Sarde in Saor — Venice's Ancient Sweet-Sour Sardines

Pat the butterflied sardines completely dry with paper towels. Season both sides with salt and pepper, then dredge lightly in flour and shake off any excess.

Heat 60 ml of the olive oil in a wide frying pan over medium-high heat. Fry the sardines in batches — do not crowd the pan — for 2–3 minutes per side until golden and cooked through. Transfer to a plate lined with paper towels and leave to cool completely to room temperature.

Wipe the pan clean. Add the remaining 60 ml of olive oil over low heat. Add the sliced onions and bay leaves, season lightly with salt, and cook gently for 35–40 minutes, stirring occasionally, until the onions are completely soft and translucent. They must not brown.

Pour in the white wine vinegar and raise the heat to medium. Simmer for 8–10 minutes until the vinegar has reduced by at least half and its sharp raw edge has mellowed.

Stir in the raisins and pine nuts. Cook for 2 more minutes, then remove from heat. Remove and discard the bay leaves. Let the saor cool completely — at least 30 minutes.

Once both the sardines and the saor are at room temperature, layer them in a deep container or glass dish with a lid: start with a thin layer of saor on the bottom, then a layer of sardines, then more saor. Repeat until everything is used, finishing with a generous layer of saor on top.

Cover tightly and refrigerate for a minimum of 24 hours. 48 hours is better: the fine bones will soften until edible and the flavors will fully merge. This rest is not optional.

To serve, remove the dish from the refrigerator 20 minutes before eating to bring to room temperature. Serve as a cicchetto with crostini or alongside polenta.