That is the famous historic restaurant, Haci Abdullah off Istiklal avenue in Taksim in Istanbul. Now what is its connection to Sultan Abdulhamid? You hear many versions: that Sultan Abdulhamid used to eat there regularly, or that he ate there once, or that he opened the restaurant and blessed it with his presence back in 1888--when it first opened. What I have been able to verify is this: none of the claims are true, but he did sign the license for the restaurant, or somebody signed it on his behalf. The (vegetarian) stuffed eggplants dish is outstanding.