The nasi lemak stall at Changi Village is the only answer ^
Its opposite the Le Meridien Changi (which is closed for renovations I think) and its also the departure point for the boats to Pulau Ubin, if you need to ask a local how to get there. Last stop for bus number 2 going east.
There are actually a few nasi lemak stalls but the one you are looking for is at the corner (International Nasi Lemak is the name IIRC)....just look for the long line of people queueing up.