Leviticus 3:2-5

2He should lay his hand on the head of his offering and slaughter it at the entrance of the Tent of Meeting. Then Aaron’s sons the kohanim are to splash the blood around on the altar.

3He is to bring from the sacrifice of fellowship offerings an offering made by fire to Adonai, the fat that covers the innards, all the fat that is on the entrails,

4as well as the two kidneys and the fat that is on them which is by the loins, plus the cover on the liver that he must remove with the kidneys.

5Aaron’s sons are to burn it up as smoke on the altar on top of the burnt offering, which is over the wood that is on the fire. It is an offering made by fire—a soothing aroma to Adonai.