Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking dish.
In a large skillet over medium heat, cook ground beef until browned. Drain excess grease. Add taco seasoning and water, simmer for 3–4 minutes until thickened.
In a large bowl, combine the seasoned beef, sour cream, salsa, soup, and 1 cup of shredded cheese. Mix until well blended.
Add half of the crushed Doritos to the bottom of the baking dish. Spoon the beef mixture evenly over the chips. Top with the remaining Doritos and the rest of the shredded cheese.
Bake uncovered for 20–25 minutes, or until bubbly and the cheese is melted.
Let it cool slightly before serving. Garnish with fresh toppings like lettuce, tomatoes, or green onions if desired.