How do warm up frozen breastmilk? Just by leaving it out or by putting it under warm water until it unfreezes?

Tamara • Mommy to my 2 beautiful baby boys, Nathan Louis💙 born August 12, 2017 and Parker Joseph May 6, 2019❤️ My whole world😍

With refrigerated milk I put it under warm water for a few minutes. Just making sure it's the same with frozen milk