Wrap the potatoes in paper towels and microwave for 7 minutes. Peel the cooked potatoes, put them in a bowl and mash with a fork. Add salt, pepper and 2 tbsp of water and combine.
Add the salmon from the can to the potato, and mash the salmon with a fork.
Mince the onion and add to the salmon and potato. Add the eggs. Mix everything so it's combined well.
Put the bread crumbs on a plate.
Heat the oil in a large non-stick frying pan over medium-high heat. Form the salmon mixture into patties, dip each patty in bread crumbs on both sides, then put on a frying pan. Note: if you don't have bread crumbs, you can just skip this step - your fish cakes will taste great anyway :)
Cook 4 minutes on one side, then flip and cook another 4 minutes on the other side.