Preheat your oven to 375°F (190°C) and grease a 9x13” baking dish.

In a large skillet, brown 1 pound of ground beef until it's no longer pink, about 6-8 minutes. Drain excess fat and set aside.

Stir in a packet of taco seasoning and one can of diced tomatoes with green chilies into the browned beef. Simmer for about 5 minutes.

In a mixing bowl, combine thawed hashbrowns, 1 cup of shredded cheddar cheese, and ½ cup of sour cream. Stir until well combined.

Spread the hashbrown mixture evenly into the greased baking dish, press down gently.

Spoon the taco beef mixture evenly over the hashbrown layer.

Sprinkle the remaining 1 cup of shredded cheddar cheese on top of the beef layer.

Bake uncovered for 30-35 minutes until the top is golden brown and bubbly.

Allow the casserole to rest for about 5 minutes before serving. Garnish with chopped fresh cilantro if desired.