Preheat oven to 375°F. Grease a baking dish and set aside.
In a large skillet over medium heat, cook ground beef until browned. Drain excess grease.
Stir in taco seasoning, tomato sauce, diced tomatoes, black beans, and corn. Simmer for 5 minutes.
Spread a layer of crushed tortilla chips on the bottom of the baking dish. Add half of the beef mixture, then a layer of cheese.
Repeat layers with remaining beef and cheese. Top with extra crushed tortilla chips.
Bake for 20-25 minutes until cheese is melted and bubbly.
Garnish with green onions and fresh cilantro. Serve hot with sour cream or salsa.