A traditional northern Italian soup, Zuppa Pavese Rossa. It’s little more than broth, a splash of passata and a piece of grilled, garlic-rubbed bread, topped with an egg and a shower of Parmigiano Reggiano, then baked until the egg is just set. It’s this kind of cooking at its best, making something delicious from what needs using up - stale bread, leftover broth and that little bit of pasta sauce at the back of the fridge.