1In food processor, place parsley and garlic. Cover; process until finely chopped. Transfer mixture to small bowl; stir in lemon peel. Set aside.
2Snap off tough ends of asparagus. In 12-inch skillet, heat 1 inch water (salted, if desired) to boiling. Add asparagus. Return to boiling; reduce heat to medium. Cover; cook 5 to 6 minutes or until crisp-tender. Drain.
3Arrange asparagus on serving plate. Drizzle with butter; sprinkle with salt and pepper. Sprinkle with gremolata.