Mishneh Torah — Positive Mitzvot מצוות עשה, Chapter 88
The full Hebrew text of Mishneh Torah, Positive Mitzvot, Chapter 88, with English translation by Maimonides (Rambam).
לאכול שיירי מנחות, שנאמר: "והנותרת ממנה, יאכלו אהרון ובניו" (ויקרא ו,ט).
To eat the remains of the meal offerings, as [Leviticus 6:9] states: "Aaron and his sons will eat the remainder of it."