Fish – redshell sushi or rødskjell sushi

ok get a very sharp knife (straight blade)

• put the blade under water
• tap the blade on the counter to rid of excess water
• cut roll in half
• repeat the process on the two portions

make sure that you're using a long knife, and when you're cutting, don't seesaw, rather it should be one fluid motion

EDIT

or do it as the comment below says :P

I have always made sure that I only defrost enough to meet the needs of the moment for sushi. If you cut the blocks into 4 to 8 rolls worth, they should defrost under running water in just fifteen to twenty minutes, just about the time it takes me to do a batch of sushi rice. That said, fish once defrosted will start to lose flavor immediately but will remain edible for 2 days. Once it starts to smell, get rid of it immediately, and I would play it very safe on that "starts to smell" the faintest whiff should be enough to send it to the bin.