yamazuke sake

I asked some of my folks about the sake in the musubi. One girl said you can make your own, cooking and flaking the salmon. Someone else said it can be bought premade, and today brought in a bottle for me. There are probably different brands from all over Japan. So I'll go check out the markets. Think this would be really good over a bowl of hot rice! And a raw egg yolk! Might be really good sprinkled over jook.