Step 1

Preheat the oven to 350 degrees F.

Step 2

In a large skillet, over medium heat, heat the oil.

Step 3

Add the onion and pepper to the skillet and cook until soft, about 5 minutes.

Step 4

Add the garlic to the veggie mixture and cook until fragrant, about 1 minute.

Step 5

Add the black beans, the corn, the chicken, and the green chiles to the veggie mixture and cook until warmed through, about 5 minutes.

Step 6

Reserve 1/2 cup of the enchilada sauce.

Step 7

Pour the remaining enchilada sauce over the veggie mixture and stir to combine.

Step 8

Spread the reserved enchilada sauce into a 9x13-baking dish.

Step 9

Layer 6 of the tortillas into the pan, overlapping to cover the entire pan.

Step 10

Pour 1/3 of the chicken mixture over the tortillas.

Step 11

Top the chicken mixture with 1/3 of the cheddar cheese and 1/3 of the Monterey Jack cheese.

Step 12

Top the cheese-covered chicken mixture with 6 more tortillas.

Step 13

Repeat the layers twice, finishing with the cheese.

Step 14

Bake the enchiladas until the cheese is melty and the sauce is bubbling, for about 30 minutes.

Step 15

Slice and serve with the sour cream, the cilantro, and the avocado.