Leviticus 7:4-6

⁴and the two kidneys, and the fat that is upon them, that which is upon the thighs, and the caul upon the liver with the kidneys, he shall take them away.

⁵And the priest shall offer them on the altar a burnt-offering to the Lord; it is for trespass.

⁶Every male of the priests shall eat them, in the holy place they shall eat them: they are most holy.