In a large skillet, cook 1 lb of ground beef over medium heat for about 7–10 minutes, stirring frequently until browned. Add 1 diced onion and cook until softened, about 3–4 minutes. Season with salt, pepper, and ½ teaspoon of garlic powder. Drain excess grease.

Stir in a 10.5 oz can of cream of mushroom soup and 1–1½ cups of frozen mixed vegetables. If desired, add ½ cup of sour cream. For a smoother consistency, add 2–3 tablespoons of milk or broth if needed.

Allow the mixture to cool for about 10 minutes to prevent the tater tots from getting soggy during baking.

Spread the beef and vegetable mixture into a greased 9x13 baking dish. Sprinkle 1–2 cups of shredded cheese over the top. Poke holes in the frozen tater tots and arrange them evenly on top of the cheese layer.

Preheat your oven to 375°F (190°C). Bake the casserole for 30–35 minutes, or until the tater tots are golden brown and crispy.

Let the casserole rest for about 5 minutes before serving to allow flavors to meld together.