Make sure the liner pan is very clean. Pour in the ultra-pasteurized milk and add the Greek yogurt starter. Mix together. Cover with foil and set the dehydration temp on the grill to 150°F/65°C and the time for 8 hours.
Use a probe thermometer to monitor the temperature periodically during the incubation period or use an instant read thermometer. See the written article for more information on this. The temp should be between 105 and 115°F/40-46°C. It will take 1-2 hours for it to reach that temp.
After the incubation time, refrigerate for several hours or until cold.
You can serve the yogurt now or strain it for Greek yogurt. See post for details.
Add your flavorings and toppings, serve, and enjoy!