Sautéed Flounder or Cod Roe

Everybody knows about shad roe—that it is delectable, available only in spring, and wildly expensive—but the roes of the humble flounder and cod are fine things, too, and cheap. Admittedly, they aren’t to be found in run-of-the-mill fish markets, but ask for them a few times and maybe the dealer will catch on. (My fish man carries winkles, conchs, cod tongues, squid, and Irish seaweed, as well as these roes and all the usual things—one of the blessings of a mixed city neighborhood.) All roe