Preheat your oven to 350°F (175°C).
In a large skillet, brown the ground beef or turkey over medium heat.
Drain excess fat from the skillet.
Add chopped onions and sauté until translucent.
Stir in the taco seasoning, black beans, corn, and diced tomatoes.
Mix well and let it simmer for 5 minutes.
In a baking dish, layer half of the meat mixture.
Sprinkle half of the crushed tortilla chips over the meat layer.
Add half of the shredded cheese on top.
Repeat the layers with the remaining meat mixture, chips, and cheese.
Bake for 20-25 minutes until the cheese is bubbly and golden.