1. Combine first 8 ingredients in a 4-quart electric slow cooker. Cover and cook on LOW for 6 hours. Stir in shrimp; cover and cook on LOW for 10 minutes or just until shrimp are done. Serve over rice. Sprinkle with green onions, if desired.
Quick Tip: To cut down on prep time, purchase prechopped onion and celery that you'll find in most grocers' produce departments. They are real timesavers.