When I first saw just the outside, it reminded me of an oyster. My impression is that it has unusual flavors and I’m convinced that not everyone would appreciate it (I’d love to try it again, though). Our friend said, when you try for the first time, it tastes odd. For the second time, it tastes better. For the third time, you crave for more…(and I agree with him!)
Since I was curious about this creature, I tried to find out what exactly it is. Its name is Microcosmus sabatieri (sea squirts) or fouska (φούσκα) in Greek, which is mainly found in the Mediterranean Sea.
Here is a picture of it (photograph borrowed from here).
Neither my husband nor his parents knew, so I wonder if it is not a mainstream food even in Greece.