Cook the potatoes in a pan of boiling water until tender, then drain.
Heat the oil in a non-stick frying pan or wok. Sweat the cabbage and the spring onions in the pan for a couple of mins. Meanwhile, chop and squash the potatoes roughly, then add to the pan along with the chives. Cook for 4-5 mins, flip it over (don’t worry if it breaks) and cook for a further 4-5 mins.
Meanwhile, bring a small pan of water to a rolling boil, then reduce the heat so it is just simmering. Crack the eggs into the pan and simmer for about 3 mins until the whites are cooked and the yolk is just beginning to set. Remove with a slotted spoon and drain on kitchen paper.
To serve, divide the bubble & squeak between 2 plates, place the smoked salmon and poached eggs on top and grind over a little black pepper, to taste.