Heat the olive oil in a saucepan, add the onion and fry gently for 3-4 minutes or until softened.
Add the garlic and Thai red curry paste and fry for one minute. Add the tomato and a splash of hot water and simmer for three minutes.
Add the fish and cook for 1-2 minutes or until cooked through.
Stir in the spinach leaves and chopped coriander. Spoon onto a plate and serve.
