shredded lettuceavocado, diced tomato, cilantro leaves and cotija cheese for garnish
Add all ingredients to a dutch oven or large stock pot and bring to a boil. Reduce heat to low, cover and simmer for 1 1/2 hours. Remove chicken from broth and set aside. Pull stems from cooked peppers, remove bay leaves from the pot and transfer the broth to a blender in batches to blend the sauce. Add the sauce back to the dutch oven, bring to a boil and cook down to 2 cups of sauce.
While sauce is cooking, shred chicken with two forks or your fingers. Add 1 cup of sauce and chicken to a bowl and combine, adding more sauce if desired.
Place small corn tortillas in a toaster oven and toast lightly. While hot, carefully bend the tortillas and place in a rack to cool into a curved taco shell shape. Layer chicken, shredded lettuce, sliced avocado, diced tomato, cilantro leaves and cotija cheese and serve with extra sauce on the side.