Step 1

Preheat the oven to 500°F.

Step 2

Heat the oil in a 10-inch oven-safe (preferably cast- iron) skillet over medium heat.

Step 3

Add the onion, garlic, cumin, and salt and cook, stirring, until the onion has softened, about 5 minutes.

Step 4

Transfer the onion  mixture to a large bowl; set aside the hot skillet.

Step 5

Add the enchilada sauce, sour cream, and 1/4 cup water to the onion mixture and stir to combine.

Step 6

Fold in the tortillas, chicken, and beans until thoroughly coated.

Step 7

Spoon the mixture into the reserved skillet and cook over medium heat until warmed through, about 3 minutes. Sprinkle the cheese all over the top and bake until the cheese is melted and bubbling, about 5 minutes.

Step 8

Let cool slightly, then top the enchiladas with sour cream, jalapeños, and cilantro (if desired) and serve directly from the skillet at the table.