Preheat the oven to 200°C (fan) or 200°C conventional.
Toss the new potatoes in the roasting tin with the olive oil and a generous pinch of salt to coat evenly.
Roast the potatoes for 20–30 minutes, until a knife slides easily into the potatoes and the skins are crisp.
While the potatoes roast, mix the chopped chives and sour cream in a bowl until combined; set aside.
Cut the smoked salmon into small strips and keep ready for assembly.
When the potatoes are cool enough to handle, gently pinch and open each one into a small baked-potato shape.
Spoon a dollop of the chive sour cream onto each potato, top with one or two strips of smoked salmon, and garnish with extra chives.