Heat oil in large kettle and sauté chicken about 5 minutes. Remove chicken. Sauté onions, celery, cabbage and garlic about 2 minutes (I started with this step since I was using precooked chicken). Add seasonings and broth. Return chicken to soup and simmer until done. Add spinach and mushrooms and simmer for 2 minutes more. My notes: I sautéed my veggies in broth. I simmered for a much longer amount of time since I was quadrupling the batch. Very healthy & tasty soup!