This began on the evening of the fourteenth (beginning of the fifteenth day) day of the first month and lasted for seven days. The first evening is the Passover Feast. 

Exodus 12

15Seven days shall ye eat unleavened bread; even the first day ye shall put away leaven out of your houses: for whosoever eateth leavened bread from the first day until the seventh day, that soul shall be cut off from Israel. 16And in the first day there shall be an holy convocation, and in the seventh day there shall be an holy convocation to you; no manner of work shall be done in them, save that which every man must eat, that only may be done of you. 17And ye shall observe the feast of unleavened bread; for in this selfsame day have I brought your armies out of the land of Egypt: therefore shall ye observe this day in your generations by an ordinance for ever. 

Celebrating this feast today can seem difficult. You would be amazed at how many things have leavening in it. But if you want to take this on and not eat any leavening for the full seven days, just make sure you read the labels on everything you buy. 

Food for the Week of Unleavened Bread 

This feast was celebrated before any of the harvests and was more of a memorial feast week than a joyful one.

The most important thing to remember about this feast week is to throw out all your leavening to make sure you don't eat anything with leavening in it.

Some foods that don't have leavening are…

Mac and cheese (most other noodles) 

Sweet potatoes 

Any kind of potatoes 

Chips

Corn chips

Corn Tortillas

All fruits and veggies

Rice

The biggest thing is to double check everything, even seasoning packets, to make sure there is no leavening in anything. 

Leavening includes: yeast, yeast extract, baking soda, baking powder, some eggs depending on how they're used (like in breads, cake, or cookies), bicarbonate of ammonia or ammonia carbonate (Baking ammonia) and other bicarbonates, and sourdough starter.