Spaghetti alla Genovese

A Ligurian dish that the Genoese insist must be made with plain dried pasta, never fresh, and certainly without eggs. Why they insist on this escapes me, but over the years I’ve noticed that Italians are quite good at pasta so I rarely ignore their advice, even if it seems pointless. The dish must also be made with home-made pesto. The inclusion of potatoes seems strange to non-Italians – starch upon starch, an anathema to many diets – but it works, the slices of potato absorbing any excess