If you crave for 'Wok Hei" fare in the wee hours, just look for Chef in Box. To think that you can find "him" at Changi General Hospital, Singapore (besides A&E Dept) is really out of the box. I have yet to try but the concept is already making me salivate!
( https://en.wikipedia.org/wiki/Wok#Wok_hei )
