How to Make It
Preheat broiler to HIGH. Place oil in a medium-size cast-iron skillet, and heat over medium, swirling to coat. Add onion, and cook, stirring occasionally, until lightly browned, about 6 minutes. Add garlic and cumin. Cook, stirring often, until fragrant, 1 to 2 minutes. Reduce heat to medium-low. Stir in drained tomatoes and salsa. Simmer over medium-low, stirring often, until slightly thickened, about 2 minutes.
Remove skillet from heat. Stir in chicken, crema, tortillas, and 1⁄2 cup of the Monterey Jack cheese. Top evenly with remaining 1 1⁄2 cups cheese.
Transfer skillet to preheated oven, and broil until cheese is lightly browned, 8 to 10 minutes. Top with avocado, and sprinkle with cilantro leaves.