Place chicken, water and 1 t. salt in a 5 qt crock pot. Cover and cook on LOW for 3 or 4 hours, JUST UNTIL TENDER. Turn chicken once halfway during cooking process. Remove chicken from crock and allow to cool. Bone the chicken in very large pieces and return the meat to the broth.
Peel the onion, cut in half horizontally and then each half vertically in half inch slices.
Heat the oil in a large skillet over medium heat and add onion, chiles, bell pepper, tomato, garlic and chipotles. Stir frequently until the veggies soften-about 5 minutes. Add the remaining 1 t. salt and the pepper. Reduce heat and simmer until totally tender. Add cream. Stir and add to chicken mixture. Cover and cook for one more hour on low.
Taste and adjust seasonings before serving with the avocado slices.