Preheat your oven to 375°F (190°C). In a large skillet over medium-high heat, brown the ground beef, breaking it up with a spoon as it cooks. Once fully browned, drain any excess grease from the skillet.

Return the skillet to medium heat. Stir in the taco seasoning mix, water, and salsa. Bring the mixture to a simmer and cook for 2-3 minutes, allowing the flavors to meld and the liquid to slightly reduce.

Remove the skillet from the heat and stir in the softened cream cheese until it's fully melted and incorporated, creating a creamy, smooth taco filling. Set aside.

Lightly crush about half of the Doritos chips into coarse pieces. Spread these crushed chips evenly across the bottom of a 9x13 inch baking dish.

Spoon the entire taco meat mixture evenly over the crushed Doritos in the baking dish. Top the meat layer with 1 cup of the shredded cheese. Crush the remaining Doritos and sprinkle them over the cheese, then finish with the remaining 1 cup of shredded cheese.

Bake the casserole for 15-20 minutes, or until the cheese is bubbly and melted and the edges are lightly golden. Keep an eye on it to prevent the Doritos from getting too dark.

Let the casserole rest for 5-10 minutes before serving. This helps it set slightly, making it easier to scoop. Serve hot with your favorite taco toppings!