Leviticus 3:8-9

8He must lay his hand on the head of his offering, then slaughter it before the tent of meeting. Aaron’s sons will splatter its blood on all sides of the altar.

9He will then present part of the fellowship sacrifice as a food offering to the Lord consisting of its fat and the entire fat tail, which he is to remove close to the backbone. He will also remove the fat surrounding the entrails, all the fat on the entrails,