Cook the Ground Beef:
In a large skillet, cook the ground beef over medium heat, breaking it apart with a spoon, until browned and fully cooked (about 6–7 minutes). Drain excess fat if necessary.
Season the Meat:
Stir in the taco seasoning and follow the instructions on the packet (typically adding water and simmering for a few minutes), or use your own homemade taco seasoning mix. Add the diced tomatoes with green chilies, black beans, and corn to the skillet. Stir to combine and let simmer for 3–5 minutes until heated through.
Assemble the Bake:
Preheat your oven to 350°F (175°C). Lightly grease a 9x9-inch or 9x13-inch baking dish. Spread half of the crushed tortilla chips evenly at the bottom of the dish. Layer the seasoned beef mixture over the chips, then sprinkle with 1 1/2 cups of shredded cheddar cheese.
Add the Second Layer:
Add another layer of crushed tortilla chips over the cheese and top with the remaining 1/2 cup of shredded cheddar cheese.
Bake:
Place the baking dish in the oven and bake for 15–20 minutes, or until the cheese is melted and bubbly.
Garnish and Serve:
Once baked, remove from the oven and sprinkle with chopped green onions if desired. Serve with sour cream, salsa, sliced olives, and jalapeño slices on the side for topping.