'Unleavened' in the Bible

So Gideon went into his house and prepared a kid, and unleavened cakes from an ephah of flour; the meat he put in a basket, and the broth he put in a pot, and brought them to him under the oak and presented them.

And the angel of God said to him, "Take the meat and the unleavened cakes, and put them on this rock, and pour the broth over them." And he did so.

Then the angel of the LORD reached out the tip of the staff that was in his hand, and touched the meat and the unleavened cakes; and there sprang up fire from the rock and consumed the flesh and the unleavened cakes; and the angel of the LORD vanished from his sight.