Preheat the oven to 200C and place a baking tray inside to heat. Place the blanched broccoli into a blender and blend until finely chopped. Pour into a bowl and add the egg yolks and mix well until combined. In a separate bowl, whisk the egg whites until soft peaks form when the whisk is removed.Then carefully fold the egg whites into the blended broccoli. Again carefully, add the cheese and season well with salt and freshly ground black pepper. Butter four ramekins and dust with flour. Spoon the soufflé mixture into the ramekins up to the brim. Sprinkle with a little extra grated cheese. Place the ramekins onto the heated baking tray and place in the oven for eight minutes, or until risen and golden. Serve.