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.