Well, we found it!! This is definitely a cheat recipe. In fact it is even a recipe but it is so good we needed to share the discovery with you. On a quest to make our Cambodian dishes more authentic we recently visited Wingyip in Manchester to buy shrimp paste etc. While we were there we found a few ready made sauces and pastes that looked interesting which (thankfully) did not contain wheat flour or gluten. One of the pastes we bought was A1 Malaysian Curry Instant Paste:
For about £1.30 I think, we seem to have found the closest thing to the dish we buy from the chippy. In fact I wouldn't be surprised if it is the sauce they use.
Here is what we did with it: