Unleavened bread is any of a wide variety of breads which are not prepared with raising agents such as yeast. Unleavened breads are generally flat breads; however, not all flat breads are unleavened. Unleavened breads, such as the tortilla and roti, are staple foods in Central America and South Asia, respectively.
Unleavened Bread. Unleavened Bread is bread that is made with nothing in it to make it rise: that is, no leavening, be it a chemical leavener, a yeast or a starter dough. Well-known examples are chapati, matzo and Mexican tortillas.