Preheat oven to 450 degrees F and line a baking sheet with parchment paper or a silicone liner.
Lay out your bread, cut side up. Baste the bread with about 1 tablespoon olive oil and spread on grated garlic.
In a large skillet add 1 tablespoon olive oil and set over medium-high heat.
Once the oil is hot, add in onions and cook for about 10 minutes until they are soft.
Add in balsamic vinegar and cook for another minute to make sure it's incorporated.
Remove the pan from the stove and add in shredded rotisserie chicken and 1 cup bbq sauce. Stir to combine.
To assemble French bread pizza, coat each slice with 1/4 cup BBQ sauce and add equal amounts of the chicken mixture to the French bread.
Top with equal amounts of cheese and bake for 5-10 minutes or until the cheese is melted and the pizza is hot.
Remove pizza from oven, sprinkle with cilantro and drizzle with extra bbq sauce if desired.