Exodus 12:37-39

37Now the 1sons of Israel journeyed from 2Rameses to Succoth, about 3six hundred thousand men on foot, aside from children. 38A 4mixed multitude also went up with them, 5along with flocks and herds, a 6very large number of livestock. 39They baked the dough which they had brought out of Egypt into cakes of unleavened bread. For it had not become leavened, since they were 7driven out of Egypt and could not delay, nor had they 8prepared any provisions for themselves.