Preheat oven to 375°F.
In a large skillet, cook ground beef and diced onion over medium heat until beef is no longer pink. Drain excess fat.
Add taco seasoning and diced tomatoes with green chilies and stir to combine.
In a 9x13-inch baking dish, layer half of the tortilla chips, followed by the beef mixture, black beans, corn, and remaining chips.
Top with shredded cheese and bake for 20-25 minutes until cheese is melted and bubbly.
Serve with sour cream, if desired. Enjoy!