Leviticus 3:2-5

2And he shall lay his hand on the head of his offering, and slaughter it at the entrance of the tent of meeting; and Aaron's sons, the priests, shall sprinkle the blood on the altar round about.

3And he shall present of the sacrifice of peace-offering an offering by fire to Jehovah; the fat that covereth the inwards, and all the fat that is on the inwards,

4and 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;

5and Aaron's sons shall burn it on the altar upon the burnt-offering which [lieth] on the wood that is upon the fire: [it is] an offering by fire to Jehovah of a sweet odour.