I have never seen the Messenger of Allah (ﷺ) hastening as much in observing supererogatory as two rak'ahs before the (Fard) of the dawn prayer.
Sahih Muslim Book 6, Hadith 117
← Previous Hadith 'A'isha reported that the Apostle (ﷺ) was not so much particular about observing supererogatory rak'ahs as in case of the two rak'ahs of the dawn prayer.

Sahih Muslim Book 6, Hadith 116 Next Hadith → The two rak'ahs at dawn are better than this world and what it contains.

Sahih Muslim Book 6, Hadith 118