I tried quite an amazing dish this evening - something that came unexpectedly and was really pretty tasty.
It was my first visit to Shimo - a Sushi joint on Clement and 23rd in the Richmond district. There was hardly anyone in there, and I struck up a conversation with the sushi chef about other SF sushi spots. I was telling him how I once had Shark Fin and Jellyfish nigiri at Hamano's, when, suddenly, he produced a small bowl filled with something odd looking and proclaimed: "This will put hair on your chest."
The bowl contained a number of 2-inch stretches of meat that looked like decaying dead leeches with warts. Yummy. He informed me that this was Sea Cucumber. Always ready for adventure, I picked one up and dropped it into my mouth.
Although they look quite soft, they are actually pretty chewy. In a good way, though, since I've never been a big fan of the chewier seafood items on Sushi menus. Apparently the sea cucumber marinates in Ponzu sauce for awhile (in my case it had been about two days) before being served, so the first taste was quite sharp and vinegary. But biting into the morsel itself offset the ponzu with a darker, rich earthy taste, and a surprising pop, as if there were pockets of air inside that burst upon bite. It really didn't taste seafoody at all - more like some strange marinated mushroom - dark and musty made bright by the lip smacking ponzu. I recommend trying it for the experience alone.
Apparently much preparation time is involved in creating this dish - all the sea-cucumbers must be peeled to get to a relatively small amount of meat inside - so Shimo doesn't carry this very often. Nor was it on the menu or list of specials. If you want it, ask the chef for a sample (I wish I could remember its Japanese name), and go soon because I don't know how much longer it will be available.