Measure beans into the slow cooker and mash until they mostly resemble a puree. You can use a blender or a food processor to do this if you’d like.
Add onions, garlic, 1 cup of chicken stock and salsa verde and stir well. Add all the remaining ingredients.
Note: Add the crushed red pepper at this time if you’re using. I’d suggest omitting if your family is sensitive to spicy foods, as the chilies and salsa provide enough kick on their own.
Cook chili on low for 4-6 hours, stirring occasionally.
Tip: If the chili is too thick for your liking, add up to 1 cup of chicken stock. Note that the chili will thicken as it cools and will be noticeably thicker the next day.
Serve with optional corn chips, sour cream, shredded cheese, diced avocado and chopped cilantro as desired.
Notes
If you want to use 2 cups shredded chicken, wait to add it until the chili is almost finished.