Preheat your oven to 400°F (200°C).
In a medium bowl, combine the shredded chicken and buffalo sauce, mixing well to coat the chicken evenly.
Place the flatbreads on a baking sheet lined with parchment paper. Brush each flatbread lightly with olive oil and season with salt and pepper.
Evenly distribute the buffalo chicken mixture over each flatbread.
Sprinkle the shredded mozzarella cheese and blue cheese crumbles on top of the chicken.
Bake in the preheated oven for 12-15 minutes, or until the cheese is melted and bubbly.
Remove from the oven and drizzle ranch dressing over the top.
Garnish with chopped green onions before slicing and serving.