Peel and rinse the tomatillos to remove stickiness, then quarter them. Prepare the onion, garlic, poblanos, and jalapeño by chopping as directed.
Heat the 6-quart stock pot over medium heat and add the olive oil. Add the chopped onion, minced garlic, and chopped peppers; sauté until the onion is translucent, about 5–8 minutes.
Stir in the quartered tomatillos. Add the raw whole chicken pieces to the pot. Sprinkle in the cumin, coriander, oregano, salt, and add the bay leaf. Pour in the chicken broth and stir to combine, pushing the chicken pieces down into the liquid.
Bring to a simmer, then reduce heat and simmer gently for 25–30 minutes, or until the largest piece of chicken is cooked through.
Use tongs to transfer the chicken to a cutting board. Remove and discard the bay leaf.
Use an immersion blender to puree the vegetables and broth in the pot until the tomatillos are mostly broken down but the mixture can remain slightly chunky.
Shred the cooked chicken with two forks, then return the shredded chicken to the pot. Stir to combine and heat through.
Taste and adjust seasoning with salt and pepper as needed, then stir in the chopped cilantro. Serve warm with optional lime wedges and sliced avocado.
