In a small ball, mix curry powder, curry paste, ketjap manis and vinegar.
Melt butter in a heated pan, add the onions and garlic and saute for one minute. Remove from heat and let cool slightly, then add salmon and sauce and mix. Reheat for one minute. Add olive oil as needed to ensure the sauce is not too dry.
When pasta is ready add to pan with rest of ingredients, mix and heat just enough.