Place the flatbread on a sheet pan. Drizzle with olive oil, then sprinkle on the garlic powder. Slice the grilled chicken into strips, then place on flatbread. Toss the mozzarella and 2 tablespoons of the Parmesan over the chicken. Bake for 10 minutes or until cheese gets melty.
While flatbread is in the oven, grab a large bowl. Rip the romaine heart into bite sized pieces, then add the Caesar dressing, croutons, remaining 2 tablespoons of Parmesan and a sprinkle of salt and pepper.
Remove the flatbread from the oven and let cool for 2 minutes. Cut in half, and place each on a plate. Top with a heaping pile of the Caesar salad and dig in!