Leviticus 4:8-10

8He shall remove all the fat from the bull of the sin offering—the fat that covers the entrails, and all the fat which is on the entrails,

9and the two kidneys with the fat that is on them at the loins, and the lobe of the liver, which he shall remove with the kidneys

10(just as these are removed from the ox of the sacrifice of peace offerings), and the priest is to offer them up in smoke on the altar of burnt offering.