Method

• 1.
  For dough, place flour, ½ tsp salt and 340ml water in an electric mixer fitted with the dough hook. Mix on low for 15 minutes or until a smooth dough forms. Wrap in plastic wrap and refrigerate for 2 hours to rest.
• 2.
  Divide dough into 4 equal pieces and roll each into a 1.5cm-thick rope, then cut into 1cm pieces. Roll each piece between the palms of your hands into a little tube with tapered ends – you only need to rub your hands back and forth a few times. Place on a well-floured tray and cover with a tea towel to prevent the pasta drying out while you make the rest.
• 3.
  For pesto, wash basil in cold water, then spin dry. Place basil, pine nuts, garlic and cheeses in a food processor and blend to combine. With motor running, gradually add oil to form a fine paste. Season.
• 4.
  Bring a large saucepan of salted water to the boil, add potato and cook for 8 minutes. Add the trofie, giving it a gentle stir so it doesn’t stick, and cook for 3 minutes. Add the beans and cook for another 2 minutes. By now the pasta should be al dente and the vegetables just tender. Drain, reserving a little cooking liquid.
• 5.
  Place the trofie and vegetables in a large bowl. Add enough pesto to coat well, then toss with a splash of the reserved cooking liquid to emulsify and bring everything together. Season and serve in warm bowls and top with shaved pecorino.