Boil the potatoes, carrots and onions. Pour water in a separate bowl of vegetables. Strain potatoes, carrots, onions and add to the milk and melted butter. Gradually pour and separated from water (as you want to be dense or liquid soup). Season with pepper and salt. Returns on low heat for 2-3 minutes. For the croutons: Cut bread into cubes. Place in a bowl and pour over them sunflower oil or olive oil (about 1 tbsp), sprinkle with garlic and mix well. Bake in the oven for 5-10 minutes until browned.