Add celery, carrots, sweet onion, garlic, 10 cups of chicken broth and all seasonings to the slow cooker. Set to HIGH for 6 hours or LOW for 8 hours.
With 2 hours remaining, add the parboiled rice and remaining 2 cups of broth.
When cooking time is done, add rotisserie chicken pieces and scallions. Stir, taste and season with additional salt and pepper if desired.
Notes
Serving size is for 2 cups of soup. Storing: Store chicken and rice soup in the fridge for up to 5 days for optimal quality. Reheat in the microwave or on the stovetop. To freeze, place the soup in freezer safe storage bags and thaw in the fridge overnight.Tip 1: You'll likely need extra broth. As the soup sits, the rice will continue to absorb broth, so you'll need to add more before serving for a brothier soup.Tip 3: Add other vegetables for a variation. Peas, green beans, corn, spinach and kale are all great additions.