Leviticus 3:9-11

9And he shall present of the sacrifice of peace-offering an offering by fire to Jehovah; the fat thereof, the whole fat tail, which he shall take off close by the backbone, and the fat that covereth the inwards, and all the fat that is on the inwards,

10and the two kidneys, and the fat that is on them, which is by the flanks, and the net above the liver which he shall take away as far as the kidneys;

11and the priest shall burn it on the altar: [it is] the food of the offering by fire to Jehovah.