Exodus 29:13

29:13 You are to take all the fat that covers the entrails, and the lobe that is above the liver, and the two kidneys and the fat that is on them, and burn them on the altar.

Leviticus 3:15-16

3:15 the two kidneys with the fat on their sinews, and the protruding lobe on the liver (which he is to remove along with the kidneys). 3:16 Then the priest must offer them up in smoke on the altar as a food gift for a soothing aroma – all the fat belongs to the Lord.