Here is the recipe for mussels on the half shell topped with a savory onion-cheese mixture and broiled until hot and bubbly. Many sushi bars make this with a rather plain recipe, using only Japanese mayonnaise but this version is tastier. You can use this same mixture to top broiled clams, oysters and even fish filets in the same way. In fact, this recipe came from my mother who smears it on French bread slices or leftover buns before broiling them for a delicious hot bread.
Fresh mussels always taste best, as long as they are fresh and healthy. If local supplies are not so reliable, turn to frozen cooked mussels on the half shell that can be found in your Asian food market. Defrost them before using.
If you can find fresh mussels, choose the ones with tightly closed shells or the ones that will shut their shells when touched. Opened shells that do not respond to touch indicates a dead mussel. Mussels begin to decompose the minute they are dead and can become toxic quickly. If a mussel feels too heavy (as compared to other healthy mussels), it might be filled with mud or sand so discard it. Keep your mussels on ice until it is time to prepare them.
Rinse the mussels carefully under running water, removing the beards or hairy filaments that are attached. Again, check for dead mussels and discard them. Place about an inch of water in a pot and bring it to a simmer. Add the mussels and cover with a lid. Steam for 10 minutes. Allow to cool slightly and then carefully remove the top shell of each mussel.
Using your fingers or a sharp paring knife, lift the mussel meat from the bottom shell. Then, put it back on the half shell and place it on a baking sheet. Continue with all of the mussels and proceed with the following recipe.
Sushi Bar Broiled Mussels
1 dozen prepared mussels on half shell
1 cup Japanese mayonnaise
1 garlic clove, minced
1 Tbsp. onion, grated
¼ cup Parmesan cheese, grated
paprika for garnish
Line the prepared mussels on a baking sheet. In a mixing bowl, blend together the Japanese mayonnaise, minced garlic clove, grated onion and Parmesan cheese. Top each mussel with a bit of the spread, about one tablespoon. Sprinkle with a little bit of paprika.
Place the baking sheet under a hot broiler for about two minutes or until hot, bubbly and slightly golden. Remove and serve hot.