Step 1

Place a rack in top third of oven; heat broiler. Place tomatillos, onion, poblano chiles, serrano chiles, and garlic on a foil-lined rimmed baking sheet (it’s okay to pack them close together). Drizzle with 2 Tbsp. oil, season with salt, and toss to combine.

Step 2

Broil vegetables, rotating pan and turning chiles halfway through, until charred and blistered all over, 13–18 minutes. Watch closely, as broilers vary wildly, and widely, in intensity.

Step 3

Transfer poblano chiles to a small bowl. Cover with a towel or plastic wrap and let sit 5 minutes. Peel off skin with paper towels (don’t worry about getting every last bit). Remove stems and seeds, then finely chop 3 chiles; set those aside for assembly.

Step 4

Transfer remaining vegetables to a blender, removing stems from serranos and squeezing garlic out of skins. Add cilantro, cumin, 1 tsp. salt, ¼ cup water, and remaining 1 Tbsp. oil. Blend until a smooth, homogenous sauce forms; you should have about 5 cups. (If your blender is small, work in batches.) Season with salt.

Step 5

Do Ahead: Salsa verde can be made 3 days ahead. Transfer to an airtight container and chill. If it thickens, add 1 tsp. water at a time until you have a thinner, pourable consistency.

Step 6

Preheat oven to 350°. Finely chop half of onion. Cut the other half into thin half-moons and set aside for serving.

Step 7

Heat 2 Tbsp. oil in a large skillet over medium. Add cumin and cook, stirring, until toasty and fragrant, about 30 seconds. Add finely chopped onion and garlic and cook, stirring frequently, until softened, 3–4 minutes.

Step 8

Add kale, stir to coat in oil, and season with salt. Reduce heat to low and stir in ½ cup water. Cover pan and cook until kale is wilted and tender, 8–10 minutes. Uncover and continue to cook, stirring frequently, until water is evaporated, about 1 minute. Add beans and reserved chopped poblano chiles and cook, stirring occasionally, until heated through, 2–3 minutes. Transfer to a large bowl and let cool slightly. Add ¼ cup salsa verde and ½ cup Monterey Jack cheese and stir to combine. Season with salt; set filling aside.

Step 9

Wipe out skillet. Heat remaining ⅔ cup oil in skillet over medium-high until hot. Working one at a time, fry tortilla, turning once and reducing heat if oil sputters, until puffed and slightly browned, about 10 seconds per side. Transfer to a paper towel–lined baking sheet or plate and repeat with remaining tortillas.

Step 10

Spread ½ cup salsa verde in a 13x9" baking dish. Pour some salsa verde into a shallow bowl or pie plate. Working one at a time, dip tortilla into salsa verde in bowl to coat both sides. Transfer to a plate, then place a heaping ¼ cup filling into the center. Roll up and place seam side down in baking dish. Repeat until you’ve used all 12 tortillas (it’s fine to arrange them very tightly in the pan). Pour remaining salsa verde over.

Step 11

Cover pan with foil and bake enchiladas 15 minutes. Uncover pan, sprinkle Cotija and remaining ½ cup Monterey Jack cheese over, and continue to bake until cheese is melted and sauce is bubbling, 12–14 minutes.

Step 12

Serve enchiladas topped with cilantro and reserved sliced onion, with lime wedges, avocado, and hot sauce alongside.