Preheat the oven to 375°F. Spray a 9 by 13-inch baking dish with cooking spray and set aside.
To prepare the sauce, heat the olive oil and garlic in a sauce pan over medium heat until the garlic becomes golden and fragrant. Add the crushed tomatoes, sauce, and spices, and stir to combine. Bring to a boil and then reduce to a simmer while you prepare the filling. Season to taste with the salt before using the sauce in the lasagna.
Meanwhile, prepare the filling by heating the olive oil in a large skillet (or saute pan) over medium heat. Add in the onion, squash, bell pepper, and jalapeño. Saute the vegetables until tender. Add in the corn and saute for another minute. In separate mixing bowl, combine the shredded chicken and cilantro. Add in the sauteed vegetables and season with salt and pepper.
To assemble the lasagna, spread a layer of sauce on the bottom of the prepared baking dish. Top with a layer of tortillas. On top of the tortillas, spread half of the filling. Top the filling with cheese and another layer of sauce. Repeat the layers of tortillas, filling, cheese, and sauce. Finally, top the lasagna with a final layer of tortillas, sauce, and cheese.
Bake uncovered for about 30 minutes until bubbly. Allow the lasagna to rest for at least 10 minutes prior to serving. If desired, serve topped with sour cream and guacamole.
adapted from My Kitchen Addiction