Preheat BBQ grill to medium high.Use the tablespoon of olive oil to brush both sides of the naan.Grill naan for 3 minutes on each side
Place olives and 6-8 teaspoons of olive juice/brine (you can mix the two kinds) in a food processor and pulse until it has a finer texture but not smooth (you'll want to still see pieces of olives).
Spread this olive tapenade across one side of each naan.
Add pieces of the mozzarella cheese.
Place the naan back on the grill and cook until the bottoms get brown and crispy and the cheese melts.Toss the arugula with the balsamic vinegar and add arugula to cooked flatbread.