This dish is from Ristorante da Gesuino in the city of Sassari on the Italian island of Sardinia.
1kg mussels, washed and de-bearded
250g ripe cherry tomatoes
1 small onion, peeled and finely sliced
1 cup fresh basil leaves
1 tbsp red-wine vinegar
Juice of half a lemon
100ml extra virgin olive oil
Put mussels in a large pot and place on high heat with a lid for 2-3 minutes until they open. Remove from heat and strain. Take mussels out of shells and place meat in a serving dish. Cut each cherry tomato in half and add to mussels. Tear basil leaves into large pieces and add to dish with onion. In a bowl whisk together vinegar, lemon juice and olive oil until well emulsified. Add to mussels and other ingredients. Season with salt and mix well. Cover dish and refrigerate for at least 2 hours, ideally 24 hours. Serve with flatbread and salad.