Leviticus 9:18-21

18Finally, he slaughtered the ox and the ram as the people’s fellowship sacrifice. Aaron’s sons brought him the blood, and he splattered it on all sides of the altar.

19They also brought the fat portions from the ox and the ram — the fat tail, the fat surrounding the entrails, the kidneys, and the fatty lobe of the liver —

20and placed these on the breasts. Aaron burned the fat portions on the altar,

21but he presented the breasts and the right thigh as a presentation offering before the Lord, as Moses had commanded.