Preheat oven to 375 degrees F. Line a large baking sheet with parchment paper or foil. Set aside.
Slice the loaf of French bread in half, lengthwise. (try to cut it as evenly as possible.) Place the two pieces of French bread on the prepared baking sheet, cut side up.
Spread the barbecue sauce evenly over both pieces of bread. Then sprinkle a 1/2 cup of Mozzarella cheese evenly over the barbecue sauce on each side of bread. Top with the cooked shredded chicken and red onion. Sprinkle the remaining cheese all over the tops.
Bake for 12 to 15 minutes, or until cheese is melted and bubbly. Carefully, remove from oven and season with salt and pepper. Let pizza rest for 5 minutes before slicing. Top with cilantro then serve. Enjoy!