01 -
Set your oven to 175°C (350°F) so it's nice and hot when you need it.
02 -
Grab a big bowl and toss in the thawed potatoes, diced onion, half the cheese, both soups, and mix it up so everything's coated well.
03 -
Spray a 23 x 33 cm baking dish with a bit of cooking spray to keep stuff from sticking.
04 -
Spread the potato mixture into your prepared dish, smoothing it out to the edges.
05 -
Sprinkle the rest of your cheese over the top and dot little pieces of margarine here and there.
06 -
Slide the dish into your oven and wait around 45 to 60 minutes, until the cheese is golden brown and you see the sides bubbling away.