Begin by chopping about 1/3 to 1/2 cup sweet onion
Add the onion to 1 1/2 pounds ground round (or chuck) in a nice sized saute' pan...cook slowly and remove all grease. Add one large can fat free cream of mushroom soup to hamburger mixture and allow to warm.
Meanwhile, peel about 6-7 nice sized potatoes, quarter them and place in large pot of boiling water. While the potatoes are cooking, measure out about a cup and a half of frozen corn...place in boiling water and cook briefly, drain and add to hamburger mixture. When potatoes are done, mash with a bit of milk until smooth...add a "lump" of butter and keep warm.
Place desired amount of mashed potatoes on serving plate and top with the hamburger mixture.