Preheat your oven to 400°F (200°C).
Place the flatbreads on a baking sheet lined with parchment paper.
Spread 1/4 cup of pesto sauce evenly over each flatbread.
Distribute the shredded chicken evenly over the pesto on both flatbreads.
Scatter the halved cherry tomatoes and fresh spinach leaves on top of the chicken.
Sprinkle the shredded mozzarella cheese and grated Parmesan cheese over the vegetables and chicken.
Drizzle olive oil over the top and season with salt, pepper, and Italian seasoning if using.
Bake in the preheated oven for 12-15 minutes, or until the cheese is melted and bubbly, and the edges of the flatbreads are golden brown.
Remove from the oven and let cool for a couple of minutes before slicing into wedges.