Preheat your oven to 350°F (175°C).

In a large skillet, cook the ground beef over medium heat until browned, breaking it apart with a spatula as it cooks. Drain excess fat.

In a large bowl, combine the cooked beef, corn, green beans, cream of mushroom soup, milk, onion powder, garlic powder, salt, and pepper. Stir everything together until well mixed.

Pour the mixture into a greased 9x13-inch baking dish, spreading it evenly.

Arrange the frozen tater tots in a single layer over the top of the beef mixture.

Place the casserole in the oven and bake for 30 minutes, or until the tater tots are golden brown and crispy.

If using, sprinkle the cheddar cheese on top and return to the oven for an additional 5 minutes until the cheese is melted.

Let the casserole cool for a few minutes before serving.