Japanese Restaurant Salad Dressing

My latest quest (besides the digital camera) is to figure out what the salad dressing at Japanese Restaurants is. Not the ginger one that's usually orange and tangy and maybe even translucent. Instead, I'm thinking of the one that is very light in color. Almost off-white...possibly a tan color, that tastes almost peanut buttery.

Can anyone help me figure this out? I believe I have tasted this sauce at Sendo Sushi on First and Tasman. It's not at Kamei Restaurant on Castro. And I can't remember if Miyakes uses this sauce or not.

I went to Ranch 99 today and the closest I came was a Sesame Salad Dressing...but it had precipitate in it as there was definitely an liquid layer underneath the more precipitate-ish layer. I also saw Miso dressing. But no Peanut Buttery dressing.

Thanks for any help!