Leviticus 4:7-8

7The priest is to apply some of the blood to the horns of the altar of fragrant incense that is before the Lord in the tent of meeting. He must pour out the rest of the bull’s blood at the base of the altar of burnt offering that is at the entrance to the tent of meeting.

8He is to remove all the fat from the bull of the sin offering: the fat surrounding the entrails, all the fat that is on the entrails,