Preheat oven to 350°F (175°C).
In a large skillet over medium heat, cook the ground beef, diced onion, and minced garlic until the beef is browned and the onion is softened, about 6-8 minutes. Drain excess fat.
Add the taco seasoning mix and 1 cup water to the skillet. Stir to combine and simmer for 5 minutes until the mixture thickens.
Remove from heat and stir in the black beans, diced tomatoes with green chilies (including liquid), and frozen corn.
Spread the beef mixture evenly in a 9×13-inch baking dish.
Sprinkle 1 cup of shredded cheddar cheese evenly over the beef mixture.
Cover the baking dish tightly with aluminum foil if freezing. To freeze, place the casserole in the freezer for up to 3 months.
To bake from frozen, preheat oven to 350°F (175°C), remove foil, and bake covered for 45 minutes. Remove foil and bake an additional 10-15 minutes until cheese is melted and bubbly.
If baking immediately, bake uncovered for 25 minutes or until cheese is melted and bubbly.
Remove from oven and sprinkle crushed tortilla chips and chopped fresh cilantro on top before serving.