Once flour has been reacted with water and rapidly baked into matzo, it is no longer subject to leavening.
en.wikipedia.org Some flatbreads, such as naan, use leavening agents; others, such as matzo, do not.
en.wikipedia.org He called it creative capitalism, capitalism leavened by a pinch of idealism and altruistic desire to better the lot of others.
en.wikipedia.org Many flatbreads are unleavened made without yeast although some are slightly leavened, such as pita bread.
en.wikipedia.org Ingredients include flour, sugar, salt, ripe banana, pineapple, cinnamon, pecans, vanilla, eggs, and leavening agent.
en.wikipedia.org