1 1/4 pound mackerel fillets 1 cup tomato sauce 2 teaspoons extra virgin olive oil 5 1/2 tablespoons butter 3/4 ounce salt-packed anchovies rinsed salt to taste 1 handful of parsley a few drops of fresh lemon juice 1 cup of potato sliced into wedges 4 crostini (toasted slices of bread) oil for frying as needed.
Soften the butter at room temperature. Clean, wash, bone and chop the anchovies, then use a fork to mash the anchovies and butter in a bowl into a smooth paste. Peel the potatoes and cut into small wedges.
Rinse in cold water, drain, dry thoroughly and fry in a pan with enough boiling oil to cover the potatoes completely (you can check the temperature by carefully dropping one piece of potato into the oil).
When the potatoes are nicely browned, remove them with a slotted spoon and drain them on a paper towel. Lightly salt the mackerel fillets and moisten with the oil.
Cook the mackerel on a hot grill for 10 minutes, turning occasionally and drizzling with lemon juice. Grill the crostini until they are golden brown and hot, then spread them with the anchovy butter.
Arrange the crostini on a serving platter and top each one with a mackerel fillet.
Sprinkle with chopped parsley and decorate with the fried potatoes in the center. Serve with a warm and flavorful tomato sauce on the side.