Musnad Ahmad 33:766

Ali narrated to us, Sufyan narrated to us, from Mujalid, from al-Sha’bi, from Jabir ibn Abdullah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said to the Jews: "I am going to ask them about the soil of Paradise, and it is white fine flour (darmaka)." So he asked them, and they said: "It is a loaf of bread, O Abu al-Qasim." The Messenger of Allah (peace and blessings of Allah be upon him) then said: "Bread is made from fine flour (darmak)."