Kamut Spaghetti with Black Beans

Soak the black beans overnight, then cover them with cold water and bring to a boil with one bay leaf. Let them cook for 2 hours, adding salt only at the end of cooking to avoid hardening their skins. When the beans are almost ready, slice the leek lengthwise, then sauté it with a teaspoon of extra-virgin olive oil. Add the tomato passata and let it cook for 10 minutes. Cook the spaghetti, then strain and toss with the sauce and beans. Top with the remaining oil.