1 pkg. lasagne noodles
Mashed potatoes (even leftovers)
American cheese (other kind of cheese can be used)
1 onion

Butter bottom of a baking dish. Cook lasagna noodles as directed. Put a layer of the cooked noodles on bottom. Next a layer of mashed potatoes, then a layer of cheese. Saute the onion in butter and pour over top of your layers. Bake 1/2 hour at 350 degrees.