Place chicken, margarine, cream of chicken soup, and onion in slow cooker. Cover and cook on high for 6 hours. Stir in carrots and celery after 5 hours of cooking
Place torn biscuit dough in slow cooker 30 minutes before serving. Cook until dough is no longer raw in the center about 25 minutes. Peas will be added in the last 10 minutes of cooking… Serve warm.