Trofie or Trenette al Pesto

1 lb. Trofie or Trenette
1 fresh potato
1/2 cup cooked string beans
Pesto prepared as follows:
1 bunch sweet basil
2 tablespoons pinoli
4 shelled walnuts
2 tablespoons grated parmesan cheese
2 tablespoons grated pecorino cheese
1 clove garlic
1/2 cup extra virgin olive oil
salt, pepper

Blend the above ingredients until uniformly creamy

Cut the potato into thin slices. Bring a pot of salt water to a boil and add the pasta and the potato. Cut the string beans into pieces and steam. Add to the pasta and potato 2 minutes before the pasta is done. Strain but save some salt water. Add the pesto and mix. Add some of the salt water if too dry. Serve immediately. Serves four. Fresh ricotta may be added to the pasta and pesto just before serving.