I made potato pies a couple of days ago and had about two cups of mashed potatoes left over.
Saute one sliced onion in two tablespoons of butter till the onions are soft.
Add the potatoes on top of the onions and flatten out.
Cook on medium heat till there is a crust on the bottom.
Turn over and flatten again until the bottom is brown and crusty.
Don’t worry if it falls apart because you can push it back together.
Sprinkle with salt and pepper.
Garnish with diced green onions.
I served this under a grilled steak with a salad on the side.