Beat together the eggs, milk, sweetcorn, flour and spring onions until you have a smooth batter. Season well.
Heat 1 tablespoon of the oil in a large, nonstick frying pan. Add half the batter to the pan in separate spoonfuls to make 6 small pancakes. Cook for 2–3 minutes on each side until golden and cooked through. Set aside on kitchen paper while you cook the remaining batter.
Pile the pancakes on to serving plates and arrange the smoked salmon and mascarpone on top. Scatter with the chives and serve.