I am looking for the japanese restaurant shrimp sauce that they put on the shrimp while they are cooking it. They usually cover the shrimp with a lid of some sort while it cooks. I think the sauce I'm looking for might be more yellow. The hint I got from our chef the last time we ate there was that it was "just like mayonnaise", but with a few other spices. I have tried making my own with egg yolks, rice vinegar, garlic and a few other spices, but haven't yet hit upon the right combination.
Any ideas??

Thanks!