Food of the Ancient World
The culture of Ancient Greece were farmers.  So as expected their diet consisted of many fruits and vegetables.  Olive trees, as now,
were plentiful then, and it was the cooking oil of choice (the other choice being animal fat).  

Examples of fruits and vegetables include olives, pomegranates, onions, figs, dates, apples, grapes, beans, various nuts and lentils.  
Meat was chickens, pidgeons, cows, fish and geese.  If you were good at hunting, you might bring back a deer or a boar.  Animals that
were domesticated (dogs and cats for examples) were not eaten, as it was considered an affront to the gods.  Fish was by far more
popular, as was all manners of seafood (shrimp, crabs, squid).

Meat wasn't a main course, or the central course, and could be hard to come by in the winter.  Fruits were plentiful, especially in the
summer and were eaten in any and all manner that they could be, while vegetables were preferred well dressed.

The more prosperous families would dine on turtle, caviar and oysters.

There were cows, so the milk we know today (whole milk from cows) would be available, but goats were more readily available, so there
was an abundance of goat's milk and cheese.

Wine was drunk liberally, though usually diluted, in honor of Dionysus.  It was traditional to offer a chalice of wine to the gods before
drinking, by pouring it out in sacrifice.  All meals were blessed through quick prayer before eating, and 2-3 meals were eaten a day.

For your sweet tooth, the Ancient world offered honey, a main ingredient in everything from bread to wines.  Candied dates and figs
were also a sweet treat.  Native herbs and garlic were used for seasoning and taste.  Honey was also used to preserve fruits for the
winter.

"Odd" things in Greek cuisine include garos (water strained from uncleaned salted fish), ruta (a bitter herb that when dried, also had
medicinal properties) and ferula (precursor to modern ferula used in Indian cooking, it was used in fried breads, tasted almost like
leeks).