Place a pot over medium-high heat. Once the pot is hot, add the oil, followed by the onions, peppers, and corn. Cook until the veggies have softened and the onion is opaque.
Add ground beef to the pan. Once the meat is browned, add chili flakes, garlic powder, ground cumin, salt, and pepper to taste. Stir to incorporate.
Stir in diced tomatoes, black beans, chicken broth, lemon juice, and cilantro, bring to a low boil, then remove from heat and set aside.
Place a layer of tortillas along the bottom of a greased casserole dish.
Top it with the ground beef mixture, followed by the shredded cheese.
Bake for 20 minutes at 357F.
Serve with a sprinkle of fresh cilantro, and enjoy :)
Video
Notes
Cover your casserole in aluminum foil for a more even cook before putting it in the oven. Remove the foil for the last 10 minutes to crisp up the top of your taco casserole.
Ensure you rest your taco casserole before you cut into it. This will allow the casserole to solidify a little, enabling it to hold its shape easier when you do cut into it and serve it up.