Leviticus 3:9-10

9‘Then he shall offer from the sacrifice of the peace offering, as an offering made by fire to the Lord, its fat and the whole fat tail which he shall remove close to the backbone. And the fat that covers the entrails and all the fat that is on the entrails,

10the two kidneys and the fat that is on them by the flanks, and the fatty lobe attached to the liver above the kidneys, he shall remove;