My granma has a nice way of picking out fat from a pot of beef stew. She freezes a metal spoon, and on top a lukewarm pot of stew, she dips it in, and the fat solidifies right on it. Works with a medal ladle with ice in it, and the cold bottom of the ladle does the same job.
There is a better way to cut sushi without plastic wrap. Just use a sharp and thin knife. Put it in a glass filled with water and a few drops of lemon juice or lemon slices. 😊😊😊 - The rice won't stick to the knife then.