Anas ibn Maalik (may Allah be pleased with him) said: The Messenger of Allah (pbuh) said:

“Whoever prays Fajr in congregation then sits remembering Allah until the sun rises, then prays two rak’ahs, will have a reward like that of Hajj and ‘Umrah.” He said: The Messenger of Allah (pbuh) said: “In full, in full, in full.”

This hadeeth was classed as hasan by al-Albaani in Saheeh al-Tirmidhi.