Place the tomatillos, jalapeños and serrano peppers on a baking sheet and into the oven under the broiler on high.
Broil for 5 minutes or until the tomatillos and peppers begin to blacken on the outside, remove and allow to cool.
In the meantime, add the olive oil to a large pot or dutch oven over medium heat.
Add the onions, cook 3-5 minutes, then add the garlic and cook for an additional minute.
Roughly chop the tomatillos and add to the pot.
Peel the black skins from the jalapenos and serranos, remove the seeds and roughly chop the peppers, then add to the pot with the green chilies, chicken broth, milk, lime juice, chili powder, cumin, salt, pepper and cilantro.
Simmer for 3-5 minutes, then use an immersion blender to puree the soup. If you don’t have an immersion blender, pour the soup from the pot into a blender, puree, then return the soup to the pot.
Add the chicken to the soup.
Mix together, cover and simmer on low for 15-20 minutes.
Top with the optional ingredients of your choice, such as sliced avocado, queso fresco and tortilla strips.
Nutrition information provided does not include optional toppings.
To make this recipe dairy-free, I recommend using plain unsweetened soy milk or almond milk instead of traditional milk. Omit the cheese as an optional topping.