Tex-Mex Lasagna

14 6-inch corn tortillas, cut into thirds
1 cup diced onion
1 cup diced red bell pepper
1 large poblano chili, diced
1 cup frozen corn kernals
2 tablespoons minced garlic
4 tablespoons unsalted butter
1/4 cup all-purpose flour
2 tablespoons chili powder
2 teaspoons ground cumin
1 teaspoon ground coriander
2 1/2 cups chicken broth
1 tablespoon lime juice
3 cups rotisserie chicken
8 ounces cheddar, shredded
8 ounces pepper jack, shredded
scallions (optional)

Preheat oven to 350 degrees. Lightly coat a 9x13-inch baking dish with nonstick spray. Arrange tortillas in a single layer on two baking sheets. Bake tortillas until slightly crisp, about 15 minutes.

Saute onion, bell pepper, poblano, corn, and garlic in butter over medium-high heat until softened, 3-4 minutes. Stir flour, chili powder, cumin, and coriander into vegetable mixture, then whisk in broth. Bring mixture to a boil and cook until thick, stirring occasionally, about 10 minutes; add lime juice and season with salt and black pepper.

Line bottom of prepared baking dish with one-third of the tortilla strips. Layer with one-third of the chicken, vegetable mixture, and cheeses. Repeat twice, using one-third of the ingredients in each layer, ending with cheese.

Bake casserole until cheese is bubbly and melted, 30-35 minutes. Remove casserole from oven and let set 15 minutes before serving.