Preheat the oven to 180°C or 350°F.
Wash the mussels, pat them dry, and set them aside.
In a small bowl, mix the ingredients.
The foil should be laid out flat and the mussels placed on it. Put about ½ tablespoon of the mayonnaise mixture on top of each mussel.
Add some shredded Parmesan cheese on top of the mussels.
Bake the mussels for 20 minutes or until they are golden brown.
Remove from the oven.
Serving Suggestions: Add some tobiko roe to the top and serve warm.