stellazio SG ya, there's this russian restaurant at far east shopping centre called shaslik or sth, their beef stew is nice..
kensongs SG Do try Borshch Steakhouse at Serangoon Gardens... cheap and good. http://lovesingaporefood.blogspot.com/2007/11/borshch-steakhouse.html
Kuali Baba SG Shashlik is not completely authentic but it's been around for ages. I haven't eaten there though. There's a proper Russian restaurant in Tudor Court (next to Tanglin Mall) - I've forgotten the name but looking for it there shouldn't be a hassle.
Herzog_Zwei SG Shashlik is actually manned by former staff from the Russian embassy in Singapore. Not authentic? Not really as the former CPPR consists of many different parts and they try to include in all the different dishes.
Kuali Baba SG My bad then, I can't remember where I read that it was also staffed by Hainanese chefs. Heck, I haven't seeen the current menu yet.