It seems like common knowledge that the prophet Yusuf was a handsome man.
Allah the Almighty says in the surah Yusuf:
So when she heard of their scheming, she sent for them and prepared for them a banquet and gave each one of them a knife and said [to Joseph], "Come out before them." And when they saw him, they greatly admired him and cut their hands and said, "Perfect is Allah ! This is not a man; this is none but a noble angel." 12:31
This verse seems to be the proof for his beauty or handsomeness. Why did the women in Sura 12.30-31 cut their hands when they saw how "beautiful" Joseph was? seems relevant here, however none of the answers give any feedback from tafsir as it seems. If any tafsir interpret it otherwise I'd be glad to know.
However what I'm asking about is that in this context I often heard a statement saying:
" Yusuf peace be upon him was given half of the beauty/handsomness "
يوسف عليه السلام أوتي شطر الجمال
What is the source -e.g. is it mentioned in a hadith?- and authenticity of this statement?