This is the classic Cantonese accompaniment to poached meats of any type.
Heat the salt and peppercorns dry in a small frying pan until you can smell the pepper quite strongly. Allow to cool, then grind coarsely. (An electric coffee grinder doubling as a spice mill is an invaluable tool in a kitchen where lots of spices are used. Don’t use it for its original purpose at all after grinding any spices unless you want to recreate the flavour of airline coffee!)