Hilchos Issurei Mizbeiach 5:2

If even the smallest trace of leaven or honey fell into the incense, it is rendered unfit. If one burnt this mixture in the Heichal, he is subject to the penalty of lashes. “Burning” only applies to the volume of an olive.

Hilchos Issurei Mizbeiach 5:3

If someone brought leaven or honey on the altar by itself as fuel, he is exempt as per Leviticus 2:12: “They may not be brought on the altar for a pleasing aroma” (i.e., as an offering). They may not be brought for a pleasing aroma – meaning an offering – but they may be brought as fuel. Even if someone burnt something that is not meant to be burned along with leaven or honey, he is subject to lashes because it’s part of an offering. [The meaning of “something that is not meant to be burned” will be explained in the next halacha.]