Leviticus 9:8-10

New King James Version

⁸ Aaron therefore went to the altar and killed the calf of the sin offering, which was for himself. ⁹ Then the sons of Aaron brought the blood to him. And he dipped his finger in the blood, put it on the horns of the altar, and poured the blood at the base of the altar. ^10 (A)But the fat, the kidneys, and the fatty lobe from the liver of the sin offering he burned on the altar, as the Lord had commanded Moses.