Clean and de-beard the mussels - scratch off the extra bumps and then rinse.
Put the mussels in a stock pot with some water on high heat.
Stir the mussels and stop the heat as soon as they have opened.
Once the mussels have cooled down, discard the empty side of the shell.
In a small bowl, mix together the butter, chopped parsley, crushed garlic and add pepper.
Fill each mussel with some of the herb-butter mixture.
In an ovenproof dish, spread the cooking salt and arrange the mussels (shell-side down). The cooking salt will enable you to lay them flat.
Grill the mussels just long enough for the mixture to melt.
Take the dish out of the oven, and generously spread the bread crumbs on each mussel.
Put the pan back under the grill a few minutes, watch carefully the so the bread crumbs become golden brown in colour and take out of the oven.
Serve and don’t forget to soak up the remaining sauce with bread after eating your mussels!