Needless to say that the fish must be at its most freshness and there is absolutely no point in thinking of having any sushi at all with any fresh raw fish otherwise. I am very lucky to have the best fishmonger at a very reasonable walking distance where I can buy whatever fresh fish and fresh fish roe I want. Everything with this sushi cake from A-Z happens in real-time. It is truly a homemade sushi cake in a flash. Here is a full guide on how to get 'sushi grade' fish and how to prepare it. Ok, but don’t panic if you do not get access to super fresh fish. There are alternatives if you are not lucky enough to be able to buy the freshest of fish, just use canned fish it’s safest. This is the beauty of it really! It allows you to get really creative with the fillings.