Preheat and Prepare - Preheat your oven to 325°F (165°C). Begin by heating a large skillet over medium-high heat. Add the ground beef and cook until browned, breaking it up with a spoon as it cooks. Once fully browned, drain off any excess fat.

Create the Filling - To the skillet with the browned beef, add the Ranch Style beans, Ro-tel tomatoes, chopped onion, taco seasoning, cream of chicken soup, and water. Stir all ingredients together thoroughly. Reduce heat to medium-low and allow the mixture to simmer for 5-7 minutes, until everything is well combined and heated through.

Assemble the Casserole - Grease a 9×13 inch casserole dish. Create the first layer by spreading half of the crushed tortilla chips evenly across the bottom of the dish. Next, add half of the meat and bean mixture on top of the chips. Sprinkle half of the shredded cheddar cheese (1 cup) over the meat layer. Repeat these layers once more - remaining chips, then remaining meat mixture, and finally the remaining cheese.

Bake the Casserole - Cover the casserole dish with aluminum foil and place in the preheated oven. Bake for 20-30 minutes, or until the casserole is bubbling around the edges and the cheese is completely melted.

Rest and Serve - Remove the casserole from the oven and let it rest for 5-10 minutes before serving. This resting period allows the casserole to set slightly, making it easier to serve. Top individual portions with sour cream and salsa before serving.