In a large skillet over medium heat, add the ground beef. Cook until browned, breaking it apart with a spoon, about 5-7 minutes.
Stir in the taco seasoning, black beans, and corn. Cook for an additional 2-3 minutes until everything is heated through.
Spray a baking dish (9x13 inches) with cooking spray. Begin layering the tortillas on the bottom of the dish, overlapping slightly.
Spoon the meat mixture evenly over the tortillas, then pour the salsa over the top.
Sprinkle half of the shredded cheddar cheese over the meat and salsa layers. Layer additional tortillas on top, creating another layer, and repeat the meat, salsa, and cheese layering until all ingredients are used. End with a layer of tortillas topped with remaining cheese.
Cover with aluminum foil and bake in the oven for 25 minutes. Remove the foil and bake for an additional 10-15 minutes, or until the cheese is bubbly and lightly golden.
Remove from the oven and let cool for 5 minutes. Top with diced avocado and sprinkle fresh cilantro before serving.
Serve with sour cream and lime wedges on the side.
Notes
Feel free to substitute ground beef with turkey or plant-based meat.