It is narrated from Abu Muslim al-Judhami (may Allah have mercy on him) that he heard Sayyiduna Abu Dharr (may Allah be pleased with him) say: "I said: O Prophet of Allah (peace and blessings be upon him)! Which part of the night is most beloved to you, if it is decreed for me to pray two rak'ahs in it? He (peace and blessings be upon him) said: 'The middle of the night, and few are those who do it.'"
No one narrated this hadith from Abu Muslim except Abu al-Ala' (may Allah have mercy on him); al-Muhajir (may Allah have mercy on him) is alone in narrating it.
In the Dar al-Haramayn edition it is like this (al-Judhami), whereas the correct form is Abu Muslim al-Jadhmi.