Preheat your oven to 400°F (200°C).
In a mixing bowl, combine the shredded chicken and BBQ sauce. Stir until the chicken is well-coated.
Place the flatbreads on a baking sheet lined with parchment paper.
Drizzle the flatbreads with olive oil and season lightly with salt and pepper.
Evenly distribute the BBQ chicken mixture over each flatbread.
Sprinkle shredded mozzarella cheese on top of the chicken.
Add thin slices of red onion over the cheese.
Bake in the preheated oven for 10-12 minutes, or until the cheese is melted and bubbly.
Remove from the oven and let cool for a couple of minutes.
Garnish with fresh cilantro before slicing and serving.