googled: suet, the hard fatty tissues around the kidneys of cattle and sheep, used in cooking and for making tallow.
Upon further reading, it seems that pork suet (猪板油) is the fatty tissues around kidney and is quite different in texture to lard, which is pretty much just melted down fat with impurities removed.
Atora seems to be the leading suet brand:
Now I'm really curious to try pastries made with suet le.
最初由 渐渐 发布 an niang said "it's available in any store, Loeb, Loblaws, SuperC, etc., in the pork sections".
It's actually just called lard, without rendering.