Preheat your oven to 350°F.
In a large skillet over medium heat, brown the ground beef and diced onion until the beef is cooked through and the onion is translucent, about 5-7 minutes. Drain excess grease if necessary.
Stir in the diced tomatoes, cream of mushroom soup, garlic powder, onion powder, salt, and pepper. Mix well and let it simmer for 2-3 minutes.
In a greased 9x13 inch baking dish, spread the beef mixture evenly on the bottom.
Sprinkle half of the shredded cheddar cheese over the beef mixture.
Layer the frozen tater tots on top of the cheese in a single layer.
Bake in the preheated oven for 25 minutes.
Remove from the oven and sprinkle the remaining cheddar cheese over the tater tots.
Return to the oven and bake for an additional 10-15 minutes, or until the cheese is melted and bubbly, and the tater tots are golden brown.
Let it cool for a few minutes before serving.