Heat oil in a medium saucepan over medium heat. Stir in onion, spring onions and red chilli pepper. Cook and stir until onions are tender, about 5 minutes. Mix in curry powder and continue to cook and stir 2 to 5 minutes.
Blend cream into the onion mixture and simmer until thickened. Mix in fish, cooking 3 to 5 minutes, until easily flaked with a fork. Season with garlic powder, salt and pepper.