ISHRAAQ NAMAAZ (nafil)
Prophet Muhammad ﷺ said, 'whoever prays Fajr in congregation, then sits remembering Allah until the sun rises, then prays two rakaats, will have a reward like that of Hajj and Umrah'. (Tirmidhi)
It is desirable (mustahab) to perform Namaaz e Ishraaq after the sun has risen to the height of a spear (approx. fifteen to twenty minutes after sunrise).
This is a bounty that Allah Ta'ala bestows upon who ever He wills.