Heat olive oil in a large pot. Stir in onion and cook over medium heat until translucent, but not brown.
Add diced sweet potato, and stir over low heat for about 4 minutes.
Add 2 cups water and simmer for a further 4 minutes. Add can of pumpkin soup. Add curry powder and seasoning, together with chopped herbs. Add coconut cream. Lastly, add cup of milk, mixed with cornflour. Simmer together for five minutes.
Remove from heat. Can either be served with vegetable chunks in sauce, or pureed in a blender.
Bring a saucepan of water to the boil and add the fettuccine. Boil for 10 minutes or until al dente. Drain and toss with yabbies or prawns. Serve in a deep bowl with a generous ladle of sauce mixture and serve.