Peel potatoes, and cook in boiling water until soft. Press to form mash.
Cut onions into small dices.
Heat some oil,fry onions, then add in corned beef and stir well. Remove from pan.
Stir corned beef and onions into hot potato mash, mix well and divide into several equal portions and shape into balls.
On a non stick pan, heat some oil and place in potato balls. Press flat with spadle and fry until both sides are golden brown.