Preheat the oven. Preheat your oven to 350°F (175°C). Lightly grease a 9×13-inch baking dish if needed.

Brown the beef. Heat a deep skillet over medium-high heat. Add the ground beef and cook until completely browned, breaking it into small crumbles as it cooks.

Drain the excess fat. Carefully drain away any excess grease from the skillet before continuing.

Season the filling. Stir the taco seasoning and diced tomatoes with their juices into the cooked beef. Mix until everything is evenly combined and heated through.

Create the first layer. Arrange half of the corn tortillas across the bottom of the prepared 9×13-inch baking dish, overlapping them slightly as needed to cover the surface.

Add the beef filling. Spoon the seasoned ground beef and tomato mixture evenly over the tortilla layer.

Finish the layers. Arrange the remaining tortillas over the beef. Spread the salsa evenly across the top, then sprinkle with the shredded cheese.

Bake. Bake uncovered for 20 to 30 minutes, or until the casserole is heated through and the cheese is fully melted and bubbling.

Rest and serve. Remove the taco lasagna from the oven and allow it to rest for about 5 to 10 minutes before slicing. Serve warm with your favorite taco toppings.