Like everything at Paul, it's a bit on the salty side, but the zingy flavors are worth the thirst you will suffer for the rest of the afternoon. The bread is just as good as the filling. It's thick but soft, lightly dusted with flour, and bursting with slices of both black and green olives. The inside is a decadent three fat slices of fresh mozzarella cheese - the soft white kind that comes in a ball, not the yellow kind that comes in a square - alternating with slices of tomato, all dribbled with pesto and grounded with a leaf of lettuce. Considering that the full-length camembert sandwich also has three slices of cheese, I consider this mozzarella sandwich to be a pretty good deal - less bread, but equal filling. It costs slightly less than the full length sandwiches, too, though the fancy ingredients (and the fact that it's Paul Bakery) keep the price relatively high: 473 yen.
It's a chain with shops around the world - they were all over London, so now I feel a bit of anglophilic nostalgia every time I visit the one on the first floor of my office building.