Put the oil in a large, non-stick frying pan and set over a medium heat. When hot, put in the onion. Stir for 20 seconds, then put in the green chilli and tomato. Stir until the onions and tomato are soft, 2-3 minutes. Now put in the coriander, eggs, salt and pepper. Stir the eggs gently until they form thick, soft curds, or are done to your taste. Remove from heat and serve immediately.