Prepare orzo according to directions, omitting salt and fat. Add peas during last 2 minutes of cooking; drain. Heat a grill pan over high heat. Toss green onions with 1 teaspoon olive oil. Cook 2 minutes on each side. Chop onions; add to orzo. Add lemon rind, lemon juice, 1 teaspoon olive oil, and salt; toss. Sprinkle with shaved Manchego cheese.
