Preheat your oven to 350°F (175°C) and prepare a 13x9 baking dish with nonstick cooking spray.

In a large skillet over medium heat, brown 1 pound of ground beef for 5–7 minutes, then add 1 chopped onion and cook until tender.

Add taco seasoning and ½ cup of water, bring to a gentle boil, and stir frequently for about 2 minutes.

Stir in a can of black beans, a can of diced tomatoes with green chiles, and ½ cup of sour cream. Heat through for about 3 minutes.

Layer Fritos corn chips at the bottom of the prepared dish, followed by a cup of shredded cheese and the beef mixture. Finish with remaining cheese on top.

Cover with aluminum foil and bake for 15 minutes, then remove foil and bake for another 5 minutes until bubbly and golden.

Let cool for a few minutes, then serve with toppings like green onions, guacamole, salsa, and jalapeños.