Beat the eggs lightly with a fork. Season with salt and pepper.
Cut the grilled pepper into thin strips.
Heat the oil or butter in a small frying pan, then set the temperature to low.
Pour in the egg and tilt the pan around to allow the eggs spread out evenly.
Scatter the pepper bits around and lay the mozzarella slices on top.
When the egg is no longer runny and the cheese starts to melt scatter the basil leaves on top, then fold the omelette in half and cook for a couple of minutes.
Serve warm with more basil leaves on top.