Melt butter in large skillet over medium heat; add pine nuts and saute 7-10 min. Remove. Add onion and garlic and saute until soft. Add mushrooms, sun-dried tomatoes. Saute 10 min. Add tomatoes and peas and cook 10 min. Cook pasta al dente, drain and toss with sauce and pine nuts. Transfer to serving dish, top with Feta and basil. Serve immediately.