A chef prepared what is touted as Russia's most expensive burger at a bistro in Krasnodar, Friday. The dish costs 5,000 Roubles (around €75; $80) and has to be pre-ordered two days in advance before being served on a velvet pillow with a glass of champagne on the side. SOT Ivan Tretiyakov, Head Chef at Yoburg Bistro (Russian): "It includes marbl