Prepare your ingredients by shredding the rotisserie chicken, dicing the onion, and draining the beans. Make sure to rinse the beans, too. Set ingredients aside until needed.
In a large dutch oven, heat olive oil over medium heat. Add onions and cook until they become translucent, about 5-7 minutes. Add a pinch or two of salt and stir to combine. Add shredded chicken and cook for another 5 minutes.
Add salsa verde to chicken and onions and stir to combine. Add beans and 6 cups of chicken broth and stir to combine. Bring mixture to a boil and then immediately reduce heat to a simmer. Cover and continue simmering for 1 hour.
After 1 hour, add cumin, chili powder, and fresh chopped cilantro. Stir to combine. Add additional cup of chicken broth, if desired.
Serve immediately with diced avocado. Leftovers can be stored in the fridge for 3 days. Do not add diced avocado to leftover soup that is to be stored - only add when serving.