Liquid nitrogen, or LN2 as it is sometimes known, is an element that freezes an object instantaneously. This speed makes LN2 a preferred technique to prepare some types of delicacies, like ice cream. Where normal refrigeration causes the cream to crystallise and sometimes harden, LN2 leaves a silkier texture.
Another way to use LN2 is by freezing fruits and flowers and smashing them into small pieces to garnish your dishes. Not only does this give your dish a unique texture, but gives an interesting look to your plate too.