What unusual ingredients was Ezekiel told to put in his bread?

"Take wheat and barley, beans and lentils, millet and spelt; put them in a storage jar and use them to make bread for yourself." - Ezekiel 4:9a

The Jews usually made their bread from wheat and/or barley. Beans and lentils were more commonly eaten as vegetables, or cooked in soups and stews, while millet and spelt were usually fed to livestock.

So why was Ezekiel asked to use this strange recipe?

Ezekiel had been taken captive by the Babylonians (c. 597 BCE). While in exile in Babylon (present-day Iraq), he was commanded by God to perform various dramatic acts to prophesy the siege and destruction of Jerusalem. Ezekiel’s use of ingredients not commonly found in bread was a demonstration of how scarce food would be during that time, forcing the people to supplement with whatever they had at hand, including the grains normally fed to livestock. God further instructs Ezekiel to limit his food intake to just 20 shekels a day (about 230g), barely sufficient to stay alive.

For the full description of Ezekiel’s actions, read Ezekiel 4-5.