PREPARE pasta according to package directions; drain, reserving 3/4 cup cooking water.
PLACE spinach, basil, cashews, garlic, lemon peel and salt in food processor; cover. Process until combined. While processor is running, add oil and 2 tablespoons water and process until finely chopped. Stir in cheese.
COMBINE pasta, 1/2 cup reserved water and spinach mixture in large bowl; toss gently to combine. Thin with additional reserved water if needed. Season with pepper. Top with additional cheese, if desired.