I found this a typical modern Passover or Seder plate:
(Assemble around table -- don't eat yet.) All recline around the SEDER table, because reclining around the table was a sign of a free man. Everything on the table has a significance.
On the SEDER plate there is:
Hard boiled egg - symbol of the suffering and oppression in Egypt. Everything else in boiling water becomes soft or disintegrates. But an egg becomes hard, like the Israelites. The more it is boiled, the harder it becomes. An egg also symbolizes New Life.
Roasted shankbone of lamb - reminds them there had to be blood sacrificed to save their lives.
Bitter herbs - horseradish - reminds them they were servants to slavery.
Greens - parsley, celery - symbol of coming of Spring which brings hope.
Salt water - reminds them of the tears they cried in Egypt.
Haroset - nut, apple, cinnamon, wine mixture which has the appearance of straw in remembrance of the mortar used to build the Treasure Cities for Pharaoh. It is symbolic of the hope of freedom that enabled their ancestors to withstand the bitterness of slavery.
Matzah - the unleavened bread that reminds them of the haste with which they left Egypt.
Oops just found the information Lisa also provided regarding Passover--Sorry to duplicate the info.
Not only is unleavened bread a vital part of the meal--all leavening must be removed from the home prior to Passover.
Every year before the Passover, an Orthodox Jewish family will eat up as much as possible all the foods in their house not processed or packaged for the Passover. This is to remove all the leaven from the house - any fermented grain product, starter dough, breads, cakes, cookies, yeast, (baking soda and baking powder). What cannot be eaten is sold to a non-Jew. Not only can a Jew not eat any leaven during Passover week, he can't have it in his house or even own any leaven. They do usually go and buy back their products after the festival. Leaven is an emblem of sin, corruption. Paul refers to it as that in 1 Corinthians 5:6-8.
The final search for leaven is made the night before the Passover (PESAH). Traditionally a candle, feather and bag are used for this final search. Every member of the family is to participate in this search. Every nook and cranny of every floor, shelf, cupboard is inspected for the minutest grain of bread crumbs or leavening. Any dust found is swept up with the feather (like a broom) into the bag for fear it might contain a grain of leavening. Traditionally, 10 pieces of leavened bread are hidden throughout the house and the ritual is not complete until the family has found the 10 pieces. All that was found is burnt the next morning before the Passover begins.
So think DaVinci got it wrong when he showed rolls--I think it would have been unleavened (Matzo) bread at the Last Supper--not raised rolls. Religious tradition (for those who choose to believe) says that the Last Supper was a Seder, and that is why unleavened bread (crackers) is used as the Communion host.