1 lb 2 oz penne, fusilli
3 1/2 fl oz extra-virgin olive oil
1 white onion, finely diced
3 tablespoons tomato paste
2 tablespoons balsamic vinegar
1 1/2 oz good-quality tinned anchovies in oil
6 1/2 oz good-quality tinned tuna in oil
freshly grated parmesan cheese, to serve
Bring a large saucepan of salted water to the boil, add the pasta and cook according to the packet instructions until al dente. Drain the pasta over a bowl, reserving the cooking water, return to the pan and set aside.
Heat the oil in a separate saucepan over a medium heat, add the onion and cook for 3–5 minutes until softened. Add the tomato paste, vincotto and anchovies together with the oil from the tuna tin, reduce the heat to low and cook gently for 5–8 minutes, until the onions are nicely caramelised. Add the tuna and a few splashes of the reserved pasta cooking water, increase the heat to high and cook for 10–15 minutes, adding extra splashes of the pasta water as you go, until the sauce has a thin paste-like consistency.
Tip the sauce into the pan with the pasta and toss together thoroughly to coat. Divide among bowls and scatter over lots of grated parmesan. Serve.