Preheat the oven to 350°F (175°C).
Place a skillet or cast iron pan on the stove top over medium heat. Add the ground beef and onion and cook for 6-8 minutes, breaking up the beef with a spatula as it cooks.
Cook until no more pink remains and the onions are translucent. If there is a lot of fat in the skillet, drain most of it with a spoon.
Add the black beans, salsa, sour cream, and taco seasoning. Stir to combine.
Let cook 2-3 minutes to let the sauce thicken.
If your skillet is not oven-safe, place the ground beef mixture into a greased 2 quart baking dish or 7x11-inch baking dish.
Top with 1 cup of the cheese. Sprinkle the corn chips on top of the cheese. Top with remaining 1/2 cup of cheese.
Cover the casserole dish with foil and bake at 350°F (175°C) for 20-25 minutes, until the cheese is melted.
Top with your desired toppings before serving, like sour cream, shredded lettuce, sliced avocados, diced tomatoes, jalapeño, pickled onions, fresh cilantro, or black olives.
Serve immediately.