Step 1

In a saucepan, combine 1/2 cup vinegar, 1/2 cup wine, 1/2 cup water, the sugar, 1 bay leaf, a pinch of salt and 3 peppercorns. Boil for 20-30 minutes to obtain a thick sauce; remove from the heat and add 2 tsp. cornstarch mixed with 1 Tbsp. water. Cook for 2-3 minutes, stirring with a whisk.

Step 2

Remove the heads from the sardines. Butterfly them and remove the innards under gently running water and open them like books. Pat dry with paper towels.

Step 3

Using the largest holes of a grater, grate the zucchini. Finely slice the onion and cook in a pan with a drizzle of oil, a pinch of salt and 1 bay leaf until soft. Add the zucchini and cook until golden. Transfer zucchini to a baking tray to cool.

Step 4

Slowly heat peanut oil to 350°F. Beat 2 egg whites in a shallow bowl. Place cornmeal mixed with 3 Tbsp. cornstarch in a second bowl. Place 12 sardines flesh side up on a flat work surface. Spoon 1 Tbsp. zucchini mixture on each sardine and cover with another sardine, keeping the skin side facing outwards. Dip each sardine “sandwich” in the lightly beaten egg whites and then in the cornmeal mixture. Fry for 2-3 minutes until golden on both sides. Drain on paper towels, salt and serve immediately with the sauce and a few mint leaves.