01 -
Set your oven to 350°F (175°C) to warm up. In a big skillet, cook the onion and beef together over medium heat until the meat browns and the onion softens. Drain off the grease, then season with salt, pepper, and garlic powder.
02 -
Stir the cream of mushroom soup, mustard, ketchup, and milk in a bowl until it's smooth. Pour this into the skillet with the beef, mixing everything together nicely. Spread the mixture out evenly in a 9x13 dish.
03 -
Scatter the shredded cheddar cheese on top of the beef mixture. Layer the frozen French fries evenly across the cheese.
04 -
Put the dish in the oven and bake for about 30 to 35 minutes, until the fries turn crispy and golden. Add extra cheese on top if you want, and bake another 5 minutes to melt it.
05 -
Take the dish out of the oven, let it cool for a few minutes, and sprinkle on any toppings you like, such as diced pickles, chopped tomatoes, or lettuce.