Preheat your oven to 350°F (175°C) and grease a 9x13 inch baking dish.

In a large skillet over medium-high heat, cook the ground beef until browned, about 5-7 minutes. Stir in diced onions and minced garlic until the onions are soft.

Stir in the taco seasoning, black beans, corn, and diced tomatoes with green chilis. Simmer for 2-3 minutes.

In a separate bowl, combine the cream of mushroom soup and sour cream until smooth and creamy.

Layer half of the meat mixture in the baking dish, followed by half of the creamy soup mixture, 1 cup of shredded cheese, and half of the crushed Doritos. Repeat the layers.

Cover with foil and bake for 15 minutes. Remove the foil and bake for an additional 10 minutes until the cheese is golden.

Let the casserole sit for 5-10 minutes before serving.