Preheat oven to 350 degrees. Bake flour tortillas on middle rack of oven until fairly crisp all over (approx 10 min) Flip over halfway through baking to ensure each tortilla is crisp all over (especially the middle). Put them under broiler for 1 minute to slightly brown (keeping them on the middle rack not too close to heating element).

Once crisp, remove from oven. Spread each tortilla with BBQ sauce to about an inch from the edge (about 1½-2 Tablespoons sauce per tortilla, or more if desired). Add thin slices of cooked chicken and red onion slices, add grated Mozzarella and cheddar cheese, then sprinkle with a few cilantro leaves.

Place pizzas on a large baking sheet on middle rack of oven; bake at 350 degrees for 5-6 minutes, until cheese has melted. Remove from heat, and cut into slices. Serve and enjoy!