1.Place borlotti beans in a large saucepan of cold water. Bring to the boil; boil 25 minutes or until tender. Drain.
2.Process nuts, garlic, parsley and pepper until finely chopped. With the motor operating, gradually pour in ¼ cup of the oil until combined. Season with salt.
3.Cook pasta in a large saucepan of boiling salted water 8 minutes or until almost tender. Drain; reserving ½ cup of the cooking water. Return pasta to pan; cover to keep warm.
4.Meanwhile, season pears. Heat extra oil in a large frying pan over medium heat; cook pear for 2 minutes each side or until golden. Drain on paper towel. Add beans to same pan, stirring for 2 minutes or until heated through.
5.Add nut paste to pasta with enough reserved cooking water for the paste to coat the pasta (do not return the pan to the heat or the nut paste will thicken and make the mixture dry). Add pears, beans and radicchio; toss gently to combine. Season.
6.Serve pasta topped with cheese and parsley sprigs, drizzled with remaining oil.