Preheat the broiler. Heat a medium cast-iron skillet over medium. Add the onion and garlic and cook, stirring often, until the onion is charred in spots, about 5 minutes. Stir in the chicken, beans, corn, enchilada sauce, chipotle and adobo sauce, cumin and half the cheese. Increase the heat to medium-high and bring to a simmer; remove from the heat.
Sprinkle with the remaining cheese. Broil until brown and bubbly, 3 to 5 minutes. Garnish with the sour cream and cilantro. Serve with the corn chips.