Cook the chicken, if starting from scratch. If you're not using leftover chicken or leftover rotisserie chicken, place chicken breast in a large saucepan and cover with chicken broth. Bring to a boil, then reduce to low heat, cover, and simmer until cooked through, 15 to 20 minutes. Shred with two forks and set aside. (A rotisserie chickens sold at most grocery stores will save you this step entirely and get dinner on the table in less time — honestly, the easiest way to make this recipe.)

2. Char the poblano and serrano peppers. Set the 2 poblano peppers and 1-2 serrano peppers on a rimmed baking sheet under the broiler, or directly over a gas flame, turning occasionally until blackened and blistered on all sides, about 8 minutes. Transfer to a bowl, cover with plastic wrap and let steam for 10 minutes, then rub off the charred skins and remove the stems and seeds.

3. Boil the tomatillos. Meanwhile, in a large saucepan, combine the 1 pound tomatillos, quartered 1/2 white onion, 2 cloves garlic and 1 cup chicken broth, bring to a boil over medium-high heat, then reduce to low heat and simmer, stirring occasionally, until the tomatillos turn olive-green and soften, about 10 minutes. Let cool slightly.

4. Blend the sauce. Transfer the peeled poblanos, serranos, tomatillos, onion, garlic, and chicken broth to a blender. Add the 1/4 cup fresh cilantro, and 1 teaspoon kosher salt. Blend until smooth.

5. Pour the mixture into a medium skillet set over low heat and whisk in the 1/2 cup heavy cream (or sour cream) until you reach the consistency of a light cream soup. Taste and adjust the salt — this creamy tomatillo sauce is your suiza sauce. Set aside a scant cup of the sauce for the chicken filling and keep the remaining sauce warm.

6. Make the chicken filling. In a small skillet, warm the tablespoon of oil over medium-high heat. Add the sliced white onions and season with salt. Cook until soft and caramelized on the edges, about 8-10 minutes. In a large bowl, combine the sautéed onions, shredded chicken, 4 ounces softened cream cheese, 1/2 cup of the Monterey Jack cheese, and the cup of sauce you set aside. Season with kosher salt and stir until creamy — this is your chicken filling.

7. Fry the tortillas. Heat 5-6 tablespoons of the oil in a medium skillet over medium heat. Using tongs, dip each tortilla in the hot oil for about 30 seconds, coating both sides of each tortilla until softened and pliable but not crisp; add more oil as needed. Drain on paper towels and repeat with the remaining tortillas.

8. Fill and roll. Preheat the oven to 375°F. Spread a scant cup of the sauce across the bottom of a 9 x 13-inchbaking dish (or casserole dish) to keep the enchiladas from sticking. Working with the warm tortillas one at a time, dip each tortilla in the sauce, coating both sides. Set the tortilla on a plate and spoon about 1/3 cup of the chicken mixture on the bottom third of the tortilla. Roll it up snugly, and place seam side down in the dish. Repeat with the remaining tortillas.

9. Sauce and bake. Pour the remaining sauce evenly over the rolled enchiladas, coating them completely, then sprinkle with the remaining 1 cup of shredded cheese. Spray one side of aluminum foil with cooking sprayCover the casserole dish tightly with aluminum foil and bake for 15 minutes. Uncover and bake 10 minutes more, until you've got bubbling, melted cheese and golden brown edges.

10. Serve. Let the enchiladas suizas rest 5 minutes, then top with desired toppings like Cotija cheese, extra fresh cilantro, and a dollop of sour cream.