Preheat oven to 400°F. Coat a 9-inch (or similar size) baking dish with cooking spray.

Heat avocado (or canola) oil in a large skillet over medium-high heat. Add beef, onion and bell pepper and cook, crumbling the beef with a wooden spoon, until it is no longer pink and the vegetables are tender, 5 to 8 minutes. Stir in corn, cumin, chili powder, garlic powder, green chiles; cook, stirring occasionally, until the corn is heated through and the spices are fragrant, about 1 minute. Remove from heat.

Arrange one-third of the tortilla wedges in the prepared baking dish, overlapping as necessary to fit. Top with half the beef mixture and ½ cup of the cheese. Repeat with half the remaining tortillas, the remaining beef mixture and ½ cup of the cheese. Top with the remaining tortillas, the remaining ½ cup cheese and tomato.

Bake until bubbling, about 20 minutes. Top the casserole with cilantro and cut into 4 servings.