Bring a large saucepan of water to the boil, add 1 tbsp white wine vinegar and reduce the heat to just below simmering.
Crack an egg into a small mug. Stir the water with a large spoon and immediately tip the egg from a low height into the centre of the swirling water. Poach the egg for 3-4 minutes.
Remove the egg with a slotted spoon and drain on kitchen paper.
Place slices of smoked salmon on pieces of toasted baguette slices.
Serve with the poached egg.
Season with freshly ground black pepper and snipped chives. Serve straight away.