Preheat oven to 350 degrees F. Spray a 9x13-inch baking dish with nonstick cooking spray; set aside.

Melt butter in a large skillet over medium-high heat. Add onion and cook for 5 minutes, or until tender. Add garlic and sauté for an additional minute.

Sprinkle flour on top and cook for 2 minutes, or until it begins to brown. Whisk in chicken broth, season with salt and cumin and continue to cook, whisking continuously, until thickened. Remove from heat and stir in yogurt and green chiles until well combined; set aside.

In a mixing bowl, combine cooked chicken and salsa verde; set aside. In another bowl, combine shredded swiss and colby jack cheeses; set aside.

To assemble, spread 1⁄2 cup cream sauce in the bottom of the prepared pan. Layer with 6 tortillas, half the chicken mixture, half the remaining cream sauce and half the shredded cheese. Repeat layers.

Bake for 30 minutes then remove from oven and top with fresh cilantro before serving.