Preheat oven to 400°F. Arrange tater tots on a baking sheet and bake for 15 minutes.
Meanwhile, sauté onions in olive oil for 3-4 minutes, add garlic for 1 minute.
Brown ground beef in the same skillet, drain fat. Stir in taco seasoning and water, simmer 1-2 minutes.
In a large bowl, combine meat mixture, black beans, corn, green chiles, enchilada sauce and 2 cups cheese.
Spray a 9×13 baking dish with cooking spray. Add mixture, top with pre-baked tater tots, then sprinkle with remaining 1 cup cheese.
Lower oven to 375°F and bake uncovered for 30 minutes until bubbly.
Cool slightly and serve with your favorite toppings!
