Peel the potatoes, cut them into chunks, then cook them in boiling salted water until they are soft.
While the potatoes are cooking, wash and roughly chop the spring onions, and cut the corned beef into chunks and set them aside.
When the potatoes are cooked, drain them and roughly mash them. You don't want it too smooth as the hash should be quite chunky.
Mix the spring onion and corned beef into the mashed potato, then spray a frying pan with some low calorie cooking spray and heat it up.
Divide the hash into 3 equal portions and serve topped with a fried egg.