Yep.<br/><br/>Basic rundown: spend a HD during a short rest, roll it and add your Con mod to your HP.  A Cook can give up to six of us an extra point.  You can spend as many HD as you want, and you can spend them one at a time to make sure you don't overspend.<br/><br/>During a long rest, you regain half your level of them, round down, minimum one.