Catoblepas Meat
From Witcher Wiki
"Conjured meat of the mysterious creature called the catoblepas".
Princess Adda demands that Geralt procure her favourite dish, but she won't tell him what it is during A Posh Reception. The witcher must then canvass the other party guests to find out what that dish is and how it is prepared. And then comes the hard part, actually getting it.
