Preheat the oven with a pizza stone to 450°. In a skillet, cook the pancetta in 2 tablespoons of oil over moderate heat, until crisp; transfer to a plate. Add the garlic, rosemary and crushed pepper to the skillet and cook for 20 seconds. Mash in the beans. Stir in the pancetta; season with salt. Brush the flatbreads with oil and spread with the bean mixture. Top with the cheese. Bake the flatbreads until the cheese is bubbling, 7 minutes; transfer to plates and serve.