Combine first 6 ingredients in a large zip-top heavy-duty plastic bag. Add lamb strips; seal bag, and marinate in refrigerator 8 hours, turning bag occasionally.
Arrange the potatoes in a vegetable steamer over boiling water. Cover and steam 10 minutes or until tender. Let potatoes cool.
Combine lamb mixture, potatoes, lettuce, celery, cherry tomato halves, and crumbled feta cheese in a large bowl; toss well.Servings: 4