Pull the chicken breasts off the rotisserie chicken while it's still warm — that makes shredding so much easier. Place the chicken in the bowl of your stand mixer and turn it on low speed for about 20–30 seconds, then bump it up just slightly until it shreds to the texture you like. If you want bigger chunks, stop sooner. If you want it finely shredded (which I recommend for enchiladas so it rolls up nicely), let it go a little longer. No stand mixer? Just shred by hand with two forks — totally fine!

In a skillet over medium-low heat, melt 1–2 tablespoons of butter. Add your diced onion and let it cook for a couple of minutes. Then add the bag of chopped spinach right into the skillet and stir it together with the onions. Cook for about 3–5 minutes until the spinach is fully wilted down and the onions have softened. It will cook down a lot — that's perfectly normal.

Add the sautéed spinach and onion mixture directly into the bowl with your shredded chicken. Sprinkle with the ¼ teaspoon of salt and stir everything together. Set aside.

In a large bowl, combine the sour cream, 3 cups of Monterey Jack cheese, cream of chicken soup, diced green chilies, and milk. Stir it all together until smooth and well combined. Give it a taste — you're looking for a creamy, savory sauce with just a little bit of heat from those green chilies. If you want more heat, this is the moment to bump it up.

Add about half of the sour cream sauce to your chicken, spinach, and onion mixture. Stir well until everything is evenly coated and the filling smells absolutely amazing — because it will. Set the remaining half of the sauce aside to go on top.

Preheat your oven to 350°F. Spray your 9x13 baking dish well with cooking spray. Spoon a good amount of the chicken filling down the center of each flour tortilla, then fold the sides in and place each one seam-side down in your baking dish. Pack them in snugly. Keep going until your pan is full, then start a second dish with the remaining filling. This recipe comfortably fills two 9x13 pans.

Spoon the remaining sour cream sauce evenly over the top of the enchiladas in each dish, spreading it all the way to the edges. Then sprinkle a little of your reserved Monterey Jack cheese over the top. You don't need a lot — there's already cheese worked into the filling and the sauce. Just enough to get a little golden, toasty layer on top.

Place your dish (or dishes) in the oven at 350°F and bake for 25–33 minutes, until the sauce is bubbling and the cheese on top is just starting to turn golden brown. Everything inside is already cooked, so you're really just heating it through and letting that top get beautiful. Keep an eye on it — every oven is a little different.

Let it rest for just 5 minutes after it comes out of the oven, then serve it up. These are wonderful all on their own, but they're also great alongside a simple green salad, some rice, or chips and salsa on the side.