01 - Preheat oven to 375°F. Lightly grease a 9x13 inch baking dish.
02 - In a large skillet over medium heat, cook ground beef and onion until beef is browned and onion is soft, about 6–8 minutes. Drain excess fat.
03 - Stir in garlic powder, onion powder, salt, and pepper.
04 - Add the cream of mushroom soup and milk to the skillet. Mix until combined, then stir in corn and peas (if using).
05 - Spread the beef and vegetable mixture evenly in the prepared baking dish. Sprinkle shredded cheddar cheese over the top.
06 - Arrange tater tots in a single, even layer over the casserole.
07 - Bake uncovered for 40–45 minutes, or until tater tots are golden brown and crispy.
08 - Let cool for 5 minutes before serving.