I've had the Hindu meal in Y and C departing internationally from SFO, SEA, LAX, ORD, IAD, LHR, FRA, NRT, SIN and ICN. My ranking (from top to bottom) would be:

SIN, far and away the leader
NRT
LHR
ORD, SFO and SEA
FRA and ICN - they don't seem to understand the concept of spice
LAX
IAD

In C, I can understand that the dessert is common to all pax. But in Y, I'm always wondering why the Hindu meal comes with some sort of pre-packaged moon rock, while even the basic "vegetarian" meal comes with a halfway decent pastry/mousse type thingie in a little tray.