I use THIS
on my KJ. Just spray it on let it sit a few mins then wipe with a cloth, works great. I've also used Windex which works well.
I also like to do this when it's a little warm, beginning or end of cooks.
Kamado Joe Classic, 18.5" WSM w/ CyberQ WiFi, [COLOR="BLUE"]22.5" OTG[/COLOR], [COLOR="Lime"]Weber SJS[/COLOR]