Put the vegetables together with a splash of wine or beer in a large pot. Place the mussels on top. Sprinkle with pepper and bring to a boil with the lid closed. Shake the mussels during cooking. When the shells are all open after about 5-8 minutes, the mussels are cooked. Serve them with baguette or fries and sauces of your choice. Check the traditional recipe for more information.