Break the eggs into a bowl and beat them with a large metal whisk. Season with a little salt and some freshly ground black pepper, then stir in the snipped chives. Drain the prawns in a sieve, then tip them on to some kitchen paper to soak up any excess moisture.
Brush a small non-stick frying pan with just enough oil to lightly coat the base and place it over a medium heat. Pour the eggs into the frying pan. As the eggs begin to set, use a wooden spoon to draw the cooked egg towards the centre. Do this 5 or 6 times, working pour way around the pan. As the cooked egg is moved, the uncooked egg will run into the gaps and begin to cook.
Scatter the prawns over the omelette and cook for a further 2-3 minutes or until the eggs are just set. Season with a little more pepper then carefully loosen the sides with a heatproof palette knife and fold the omelette over. Slide it on to a warmed plate and serve with a large, lightly dressed salad.