Thareed is the best food as this Hadith explains :
ثبت في الصحيحين عنه ـ صلى الله عليه وسلم ـ أنه قال: فضل عائشة على النساء كفضل الثريد على سائر الطعام)
In the Sahi'hain, it is narrated that Messenger of Allah Sallallaho Alaihe Wasallam said "The Virtue of Aishah (Radi Allaho Anha) as compared to other women, is like the virtue of Thareed as compared to the rest of foods".
Tibb-e-Nabawi diet recommends neutralizing the nature of foods, hot with cold, dry with wet.
Mutton soup has meat which is hot, oil is hot, and spices are hot, making Thareed with wheat bread becomes invalid because wheat itself is hot and it can’t neutralize the heat of mutton/yakhni.
Thareed was simply mutton soup/Yakhni without heavy spices, and
because Barley bread was the staple diet during Khairul Quroon, Thareed was
exclusively prepared with Barley bread (خبز
الشعير)
Barley is the grain
chosen by Allah for your beloved Prophet صلى
الله عليه وسلم, barley bread is cold natured, hence neutralizes the hotness of
mutton soup & THAREED having barley bread is the only VALID combination.