Directions

1. Preheat oven to 375 degrees F. Coat a large rimmed baking sheet and two 8-inch-square baking dishes with cooking spray.
2. Peel the eggplant; slice into 1/4-inch-thick rounds. Halve the rounds (or quarter, if large). Arrange in a single layer on the prepared baking sheet; brush 1 Tbsp. oil over the eggplant. Bake, turning once, until the eggplant is just beginning to brown on the edges, 10 to 15 minutes. Let cool.
3. Heat the remaining 1 Tbsp. oil in a large nonstick skillet over medium-high heat. Add onions and cook, stirring, until soft, about 10 minutes. Add garlic, chili powder, oregano, onion powder, and cumin; continue cooking just until fragrant, about 30 seconds. Stir in tomatoes, beans, chiles, and cilantro. Set aside.
4. To assemble the casseroles: Cover the bottom of each baking dish with 1/4 of the tortilla pieces. Spread 1 cup of the tomato-bean mixture over the tortillas, then sprinkle each with 1/4 cup Cheddar. Top each with a layer of 1/2 of the eggplant pieces, then layer each with 1 cup of the tomato-bean mixture. Divide the remaining tortilla pieces and remaining tomato-bean mixture between the casseroles, then sprinkle each with 1/4 cup Cheddar. Cover both dishes with foil. Label and freeze one casserole for up to 1 month.
5. Bake the remaining casserole until bubbling, about 30 minutes.
6. Uncover and continue baking until the cheese is lightly browned, about 10 minutes more. Let stand for 5 minutes before cutting.