What is the meaning of "hollowing out the Basmala" as a way of revering it?

We did not come across the Hadith with the wording: "Whoever writes the Basmala, inks it, and magnifies it." A similar Hadith has been narrated: "Whoever writes 'Bismillahir Rahmanir Rahim' beautifully, in magnification of Allah, Allah will forgive him." This was narrated by Abu Nu'aym and Ibn Ashtah, and Al-Suyuti declared it weak.