Step 1

Adjust broiler rack to 8 inches below element and preheat broiler to high. Place poblanos, onion, tomatillos, serranos, and garlic on a foil-lined rimmed baking sheet. Place under broiler and broil, turning vegetables occasionally, until tomatillos are completely softened and lightly charred, about 10 minutes. Transfer tomatillos to a bowl. Continue broiling until poblanos are charred on all sides, about 2 minutes longer. Transfer to a separate bowl and cover tightly with foil. Continue broiling until onion, Serranos, and garlic are softened and charred, about 5 minutes longer. Transfer to bowl with tomatillos along with any juices and set aside.

Step 2

Adjust oven rack to middle position and set oven to 375°F. Add chicken stock to bowl with poblanos and peel poblanos while submerged in stock. Transfer flesh to bowl with tomatillos, leaving skin and seeds with the stock. Strain the stock through a fine mesh strainer into the bowl with the tomatillo/pepper mixture. Discard skins and seeds. Add cilantro to mixture. Set mixture aside.

Step 3

Season chicken pieces on all sides with salt and pepper. Heat oil in a large Dutch oven over high heat until shimmering. Add chicken skin side-down and cook without moving until well browned on first side, about 6 minutes. Flip chicken and continue cooking until lightly browned on second side, about 2 minutes longer. Transfer chicken to a bowl and pour off excess fat from Dutch oven, reserving any brown liquid.

Step 4

Add tomatillo/pepper mixture to the Dutch oven and scrape up any browned bits from the bottom. Using an immersion blender, puree mixture into a chunky sauce. Season to taste with salt and pepper. Return chicken to pot, bring to a simmer, cover with lid slightly ajar, and simmer until chicken is cooked through, about 15 minutes. Meanwhile, wrap tortillas in aluminum foil and place in oven to warm.

Step 5

When chicken is cooked, remove from heat and transfer chicken to a large bowl using tongs. Allow to rest until cool enough to handle. Shred chicken into thin strips, discarding skin and bones. Add 1 cup of sauce, half of cheese, and half of Mexican crema to chicken and toss to combine. Season to taste with salt and pepper.

Step 6

Remove tortillas from oven and unwrap. Spread 1/3 of the remaining sauce in the bottom of a 13- by 9-inch casserole dish. Dip each tortilla in the remaining sauce and stack on a cutting board. Working one tortilla at at time, place 2 tablespoons of chicken filling in a line down the center and roll up tightly. Place in the casserole dish seam side-down. Continue until all the tortillas and filling are used (the casserole will be tightly packed).

Step 7

Spread remaining sauce on top of enchiladas and lay the remaining cheese down in a line through the middle of each row of enchiladas. Cover tightly with aluminum foil and bake for 15 minutes. Remove foil and continue baking until cheese is lightly browned and bubbly, about 10 minutes longer.

Step 8

Remove enchiladas from oven, drizzle with remaining crema, sprinkle with chopped cilantro, and serve immediately.