Leviticus 3:9-11

9From the sacrifice of fellowship offerings he shall bring a gift made by fire to Adonai. Its fat—the entire tail fat cut away close to the backbone, along with the fat that covers the innards and all the fat that is on the entrails,

10as well as the two kidneys and the fat that is over them which is by the loins, plus the cover on the liver that he is to remove with the kidneys.

11The kohen is to burn it up as smoke on the altar—as a food offering made by fire to Adonai.