Preheat your oven to 375°F and lightly grease a 9x13-inch baking dish with cooking spray or a thin layer of oil.

To make the enchilada sauce, heat the olive oil in a medium saucepan over medium heat. Once the oil is warm, whisk in the flour and let it cook for about one minute, stirring constantly so it doesn't burn. Add the chili powder, cumin, garlic powder, onion powder, oregano, smoked paprika, and salt, stirring everything together until fragrant, about 30 seconds. Slowly pour in the chicken broth while whisking continuously to prevent lumps from forming, then stir in the tomato paste. Bring the sauce to a gentle simmer and let it cook for 5 to 7 minutes, stirring occasionally, until it thickens enough to coat the back of a spoon. Remove from the heat and set aside.

In a large mixing bowl, combine the shredded rotisserie chicken, black beans, corn, sour cream, cumin, chili powder, garlic powder, salt, pepper, and 1 cup of the Monterey Jack cheese. Mix everything together until well combined.

Spread about 1/2 cup of the enchilada sauce evenly across the bottom of your prepared baking dish. This prevents the tortillas from sticking and adds a great layer of flavor underneath.

Lay one tortilla flat on your work surface and spoon about 1/3 cup of the chicken filling down the center. Roll the tortilla up snugly and place it seam-side down in the baking dish. Repeat with the remaining tortillas and filling, fitting all eight rolls tightly side by side in the dish.

Pour the remaining enchilada sauce evenly over the top of the rolled tortillas, making sure to get it all the way to the edges. Sprinkle the remaining 1/2 cup of Monterey Jack cheese and all of the cheddar cheese over the top.

Cover the dish tightly with aluminum foil and bake for 20 minutes. Remove the foil and continue baking for another 5 minutes, or until the cheese is golden and bubbling around the edges. Let the enchiladas rest for 5 minutes before serving, then top with fresh cilantro, sliced jalapeños, and a dollop of sour cream.