Al-Kāfi - Volume 6 > The Leek
Hadith #3

سَهْلُ بْنُ زِيَادٍ عَنْ مُحَمَّدِ بْنِ الْوَلِيدِ عَنْ يُونُسَ بْنِ يَعْقُوبَ قَالَ رَأَيْتُ أَبَا الْحَسَنِ ( عليه السلام ) يَقْطَعُ الْكُرَّاثَ بِأُصُولِهِ فَيَغْسِلُهُ بِالْمَاءِ وَ يَأْكُلُهُ .

3. Sahl ibn Ziyad has narrated from Muhammad ibn al-Walid from Yunus ibn Ya’qub who has said the following: “I saw abu al-Hassan, ‘Alayhi al-Salam, cut leeks from their roots, wash with water and eat.”