Leviticus 3:8-9

⁸and he shall lay his hand upon the head of his oblation, and kill it before the tent of meeting: and Aaron’s sons shall sprinkle the blood thereof upon the altar round about.

⁹And he shall offer of the sacrifice of peace-offerings an offering made by fire unto Jehovah; the fat thereof, the fat tail entire, he shall take away hard by the backbone; and the fat that covereth the inwards, and all the fat that is upon the inwards,