Kosong

Just blanched "Choy Sum" vegetable. We often ask for our vegetables to be just blanched without any salt, soy sauce and oil. 

We use the word "kosong", the Malay word for zero and the staff would understand that we do not want anything to be added to the vegetable. When ordering drinks like barley water and lime juice, we also use the word "kosong" to mean that we do not want any sugar or syrup in the drinks and they would understand.