Pru, you required this recipe and we made it today for our rice noodle rolls at home today. Of course I did not taste the sauce you tasted so I will not put the amount of each item but leave that to you.
Dark soy sauce (this for color not as much for its saltyness)
Chinese Rock sugar
Cooked vegetable oil it is very important that you heat the oil until it get a little darker than oil that comes out the bottle.
Place the dark soy sauce in a saucepan and simmer over low heat and add Chinese rock sugar (this comes in pieces so measuremnnt is a little hard). Warm until the sugar is dissolved and then add a amount of cooked oil and a samll dash of sesame oil for favor.
This should be close to the one they use in a dim sum teahouses. Just adjust the ingredients to meet you taste. This is real basic and if you want I can gave you my measure but I am sure you will not need it.