Singapore fried noodles is a dish of stir-fried rice vermicelli seasoned with curry powder and vegetables typically found in Asian eateries around the world. It can be served both vegetarian or with slices of meat such as chicken, prawns, roast duck, barbeque pork and so on. It is a very popular dish all over the world but interestingly it is not an authentic cuisine from Singapore. Nevertheless it is full of flavour and you can alter the ingredients to make it your very own recipe.
I have never seen much of a "sauce" added to Singapore noodles. They are, in every recipe I have ever seen, a rather "dry" concoction. In fact, no sauce at all. I must add that Singapore Noodles are a favourite of mine, but I didn't think that any sauce was a part of them. I know that they are popular throughout many countries and that people are very particular in that they like the recipes to stay much the same. Can't really argue with you if your father is a chef, but I remain very faithful to the recipe that I have followed for maybe 40 years.