Heat the oil over a medium high heat and fry the onions until they soften. Add the tomatoes and chillies and cook until softened. Meanwhile beat the eggs in a bowl.
Add the turmeric and chilli powder to the onion and tomato mix, sir for 30 seconds and then pour in the beaten eggs. Reduce the heat to medium low and keep stirring until the eggs are softly set.
Add the salt then check the seasoning. Garnish with coriander and serve warm.