Lightly whisk the eggs in a small bowl. Season with salt and pepper.
Finely chop the spring onions and the red pepper ( and chilli). Grate the cheese and set aside. Halve the tomatoes.
Heat the oil in a small frying pan. Add the chopped veggies (except the tomatoes) and sauté for 5 minutes until they’ve softened. Add the tomatoes and cook for another 2-3 minutes.
Add the eggs mixture, allowing it to spread out evenly. Cook for about 5 minutes over medium heat, or until the egg is almost set.
Sprinkle over the cheese, turn the heat down and cook for a couple of minutes. Scatter some basil leaves on top, then carefully fold the omelette in half with a spatula. Let the cheese melt, then cut the omelette in half and serve.