Ingredients
Method
- Pound the garlic with the salt in a mortar to a paste. Add the pine nuts and pound until creamy.
- Add the basil a handful at a time, grinding in a circular motion until you have a green paste.
- Stir in both cheeses, then the olive oil gradually. (Or pulse briefly in a food processor, without overworking.)
- Bring a large pot of salted water to the boil. Add the potatoes and cook for 5 minutes.
- Add the pasta and green beans and cook until the pasta is al dente.
- Reserve a cup of cooking water and drain. Toss the pasta, potatoes and beans with the pesto off the heat, loosening with a splash of cooking water.
Notes
Never heat pesto. The warmth of the pasta is enough, and cooking turns the basil dark and bitter.