Switch off Espresso Machine 30 minutes after I switched it on

I think I have an easy question, but I can not find the answer. I have a Philips Hue power switch that is attached to my espresso machine. What I would like to do is create an automation that will switch off the espresso machine 30 minutes after I’ve switched it on. Preferably by using the HomeKit app. Any one an idea? Am I missing the obvious?