Silicone tubing is what I use. I think its temp rated to over 400*F and its easy to clean. I got it from one of the vendors on here.
"Look, let me explain something to you. I'm not Mr. Lebowski. You're Mr. Lebowski. I'm the Dude. So that's what you call me. That or His Dudeness... Duder... or El Duderino, if, you know, you're not into the whole brevity thing." -The Dude