Preheat your oven to 350°F (175°C).

In a large skillet over medium heat, add the ground beef. Cook until browned, breaking it apart with a spatula. Drain any excess fat.

Add the chopped onion, bell pepper, and garlic to the skillet with the ground beef. Cook for about 5 minutes, or until the vegetables are softened.

Stir in the taco seasoning and beef broth, mixing well to combine. Let it simmer for about 2 minutes to thicken slightly.

Stir in the can of diced tomatoes with green chilies and the black beans. Allow the mixture to cook for an additional 2-3 minutes.

In a 9x13 inch baking dish, spread half of the crushed Doritos as the bottom layer. Spoon the beef mixture over the Doritos evenly.

Spread the sour cream over the beef layer. Sprinkle 1 1/2 cups of shredded cheddar cheese over the sour cream.

Add another layer of the remaining crushed Doritos, followed by the remaining 1 ½ cups of shredded cheddar cheese.

Place the baking dish in the preheated oven and bake for 20-25 minutes, or until the cheese is melted and bubbly.

Remove the casserole from the oven and let it cool for a few minutes before serving. For extra flavor, top with salsa and sour cream, and garnish with fresh cilantro. Enjoy!