You have quite a few options for Greek food when you're in this area, but Pantheon has to be one of my favourites. The restaurant is known for two things: (1) fresh seafood, and (2) really huge portions. The grilled calamari is one of my favourites - none of that chewy rubbery stuff, and as mentioned, the portions are huge!
If your waistline can take it, the Saganaki (flambeed Kefalotiri Cheese) is a must. They flame it up table side, giving you an entertaining show before you devour a gigantic block of bubbling melty cheese. I'm literally drooling just typing this out!
And like everyone says, there is a complimentary slice of honey cake at the end. Not too sweet, and wraps up the meal nicely.