הלכה על מנחות 109:6

The laws of the commandment: That which they, may their memory be blessed, said (Menachot 52b) that all meal-offerings that are offered on top of the altar come [as] matsa, as we said. And so [too, that] the remainders of the meal-offerings that the priests eat are not eaten chamets - even though [the priests] are permitted to eat them with any food or with honey - as it is stated (Leviticus 6:10), "You shall not bake their portion chamets," and [included] in its understanding is [that] even their portion shall they not render chamets. And if he renders its remainders chamets, he is lashed. And we administer lashes for each and every doing within it. How is this? [If] he kneaded it chamets or set it up chamets or cut it up chamets or broke it up chamets or baked it chamets, he is lashed - as it is stated, "you shall not make chamets," "you shall not bake chamets," to make liable for a single action in making it chamets; [he is] liable for lashes. And we do not dampen wheat kernels of meal-offerings lest they become chamets (Rashi on Pesachim 36a). And nonetheless they, may their memory be blessed, said (Menachot 55a) that baked meal-offerings were kneaded in lukewarm water, and they would guard them that they not become chamets, as priests are alacritous. And leaven and honey are forbidden (forbid) with the smallest amount, as it is stated, "you shall not burn from it" - meaning to say, even the smallest amount. And he is not liable unless he burns them with the offering or for the sake of the offering (Mishneh Torah, Laws of Things Forbidden on the Altar 5:1). And it is one whether he burns them by themselves or their mixture - he is lashed (Menachot 58a). But if he burned them on their own for the sake of [fire]wood, he is exempted; as it is stated (Leviticus 2:12), "upon the altar they shall not be brought up as a pleasing smell" - for a pleasing smell you shall not bring up, but you may bring up for the sake of wood (Zevachim 76b). And the rest of its details are elucidated in Tractate Menachot.

He prohibited us from baking the remainders of the meal-offerings leavened (chametz). And that is His saying, "It shall not be baked leavened; I have given it to them for their portion" (Leviticus 6:10): [It is] as if He would be saying that their portion - which is the remainders of the meal-offerings - not be baked leavened. And one who bakes it leavened is liable for lashes - as it appears in the language of the Mishnah (Menachot 55a) - they said, "And we are liable for its baking." And the regulations of this commandment have already been explained in the fifth [chapter] of Menachot. (See Parashat Tzav; Mishneh Torah, Sacrificial Procedure 12.)