How to cook
Cut the potatoes into cubes and the leeks into small pieces. Pour them in boiling water and add the broth and butter.
Once they have softened well, remove the soup from the heat once it is cooked and strain it while it's still hot.
For the croutons: Cut the dry bread into cubes, sprinkle them with spices and olive oil. Mix them well and bake them at 390°F (200 degrees) in the oven until they aquire a golden color (for about 20 minutes).