History of Greek Food

English version of  Harun’s arabic description, A. Dalby, Flavors of Byzantium, p.118-9

As you already  read, there was a gold table for the emperor and there were gold  dishes, dishes encrusted  with pearls and rubbies, music, an organon  and everything that could impress the others.  Communal chanting was not unfamiliar during those Christmas banquets. At another banquet,  attended by the patriarch, abbots and monks, the beef was accompanied by chanting directed by two domestics. ”The hymns were a way both to create and express church consent to imperial rule, but also to transform the banquet into a Christian meal, a kind of hierarchical agape. non-communal chanting was sometimes performed at banquets by choral singers placed behind curtains, praising the emperor in every key.” (Eat, drink and be merry)

Harun didn’t described the food. Such description was apparently viewed as inappropriate.
But, Theodoros Prodromos, writer of  the 12th century, well know for his prose and poetry, mentions Christmas in his verses. December: I hunt hares, enjoyment from the wild; I fill my dish with tasty partridges, and I celebrate the Feast of Nativity, which is the greatest feast of the Word of God. Avoid taking generous amounts of  foods, I say, and reject the melancholy cabbage.” ( Verses on Dietary Rules, Ideler 1841, v.1, p.420)
According to the dietary calendar attributed to a certain sophist Hierophilos, Byzantines should follow those recommendations:  December~ During this month do not eat cabbage  or water mint. Meats as for November, similarly with fish and vegetables and fruits and wine and pulses and leek broth… Do no eat lentils. Take fenugreek soup in moderate amount. Do not eat caper and green olives in brine (kolymvades); eat black olives in honey vinegar and sinapis…. (ibid, p. 417)
Hierophilos recommends the following food in December:
Deer, beef, hare, male goat, wild boar, wild goats, gazelle and all game birds; lean meat, double cooked, hot and spicy, and suckling animals. 
Eat any fish except the wet ones; do not eat rainbow wrasse and gugdeon. Use pungent flavours, such as pepper, leeks and mallow. Avoid  broad beans, lentil and lupins. Among fruits don’t eat dates and bay berries; eat the rest of fruits. Drink old and flavorful wine. 

Now, you can imagine what the emperor might have eaten…. 

*Liliand Simeonova, In the depths of tenth-century byzantine ceremonial: the treatment of Arab prisoners of war at imperial banquets, BMGS 22 (1998), 75-104.