@Роберт Иванов Hummm I know and love “плескавица.” I wouldn't say it's a hamburger exactly but it's tasty. I'll definitely check out Pala Burger.  Speaking of pleskavitsa, the NYT ran an article about the dish last winter titled "<a href="http://www.nytimes.com/2010/01/20/dining/20balk.html?ref=dining" rel="nofollow">The Balkan Burger Unites all Factions</a>."