Likutei Halakhot, Orach Chaim, Laws of Passover 5:5/ליקוטי הלכות·אורח חיים·הלכות פסח ה׳:ה׳

1And this is matzah, which is the aspect of a very great light, and [it] is baked immediately because the light is formed immediately on high before it becomes "leavened." For chametz is the aspect of the realm of form, in which there are two qualities (Yoma 72b): "If one merits, it becomes an elixir of life for them, if one does not merit [it becomes an elixir of death for them]." Because chametz is the aspect of the Tree of Knowledge of Good and Evil, which contains two potentialities; for chametz is the aspect of formation, when [the dough] begins to rise and take shape, as the Sages said, that the sign of dough rising is [that it begins to look like] (Pesachim 48b) "the antennae of locusts." But matzah is the aspect of baking and taking the shape of the undifferentiated light, a quality of blessing, before it reaches the stage of leavening and begins to take shape below.