Egg pasta and pesto together is a piece of cooking genius really, and just about the only successful tweak you can make is to add a few green beans and some very thinly sliced potato – like they often do in Genoa.
If you haven’t had it before, try it – you’ll like it, and it’s really quick and easy.
Bring a large pan of water to the boil. Meanwhile, crush the pine nuts in a pestle and mortar with the garlic. Scoop out, put to one side, then put the basil in the mortar with a pinch of sea salt and bash until it turns into a green paste. Return the bashed nuts and garlic to the mortar with the lemon juice, a few tablespoons of oil and half the pecorino. Stir together and season well with salt and a little pepper.
Peel the potatoes, discarding the peel, then continue stripping the potato with the peeler until you have a pile of thin potato strips.
Add some salt to the boiling water and add the tagliatelle, the trimmed beans and the potato strips. Cook for 2–3 minutes until the beans are cooked but still have a slight bite, the pasta is al dente and the potatoes are cooked through. Drain in a colander, reserving a little of the cooking water.
Toss the cooked pasta and vegetables in a bowl with the pesto. Taste and season again, if necessary. Add a little of the reserved pasta cooking water to moisten the sauce if it’s a little thick and claggy. Serve sprinkled with the remaining pecorino and extra basil.