Preheat broiler to high heat. Remove paper skins and stems from tomatillos and wash under warm water to remove sticky residue. You can leave the garlic skin on for broiling. Place the tomatillos, garlic, and poblano on a baking sheet and broil about 6-10 inches away from heat for 6 minutes. Flip tomatillos and remove the poblano and garlic if softened and charred in spots. Peel skin off garlic. Continue broiling the tomatillos until softened and charred in spots, another 6 minutes.
Add the charred tomatillos, garlic, and poblano to a large pot or dutch oven along with the chopped shallots and saute over medium heat about 2 minutes until the shallots have softened. Add 4 cups of broth, cumin, oregano, coriander, and salt. Stir to combine.
Bring the soup to a boil over medium high heat, then decrease the heat to low to simmer for 10 minutes. Add chopped cilantro. With an immersion blender, blend the soup in the pot till it reaches your desired consistency (I like mine smooth). If you don't have an immersion blender, carefully transfer the soup to a blender. You may need to work in 2 batches. Stir in chicken and adjust any seasonings to your liking.
For homemade tortilla strips - Preheat the oven to 400 degrees ℉. Brush both sides of the tortillas with oil (olive oil or avocado oil), then slice into strips and bake for about 7-10 minutes until light brown, flipping halfway through. They'll crisp up as they cool.
Notes
Canned tomatillos can be substituted for fresh, but fresh are preferable. You can also use about 24oz salsa verde or green enchilada sauce as the base instead of the fresh tomatillo blend, but flavors will vary!
Chicken breasts can be cooked in the soup if not using cooked chicken. Blend the soup ingredients till smooth before cooking, then add in the raw chicken and simmer for about 20 minutes, or until cooked through. Remove the chicken and shred it with two forks (it should shred easily if cooked through) , then return to the pot.
For vegetarian/vegan, simply leave out the chicken.
If short on time, use crushed tortilla chips instead of the homemade strips.