The Provençal dish known as brandade de morue is a great example of how to elevate modest ingredients like salt cod and potatoes—in this case, by whipping them with milk, olive oil and garlic until luxuriously silky. Jacques Pépin's extra step of serving the dish au gratin (browned, with cheese on top) makes it that much more delicious.Recipes from Essential Pépin by Jacques Pépin. Copyright © 2011 by Jacques Pépin. Reproduced by permission of Houghton Mifflin Harcourt. All rights reserved. More Delicious Gratins
Put the salt cod in a bowl and cover with 1 inch of cold water. Refrigerate for 24 hours, changing the water 4 times.
Put the potatoes in a large saucepan, cover with water and boil over moderately high heat until tender, about 30 minutes. Drain and let the potatoes cool to warm.
Meanwhile, drain the cod and transfer to a saucepan. Add 2 quarts of water; bring just to a boil. Drain the cod and rinse out the pan. Return the cod to the pan, add 4 cups of water and bring to a boil. Simmer over low heat for 5 minutes. Drain the cod and return it to the pan, add the milk and garlic and bring to a boil. Cover and simmer for 10 minutes.
Peel the potatoes and break into chunks; transfer to a food processor. Add the cod, milk, garlic cloves, lemon zest, lemon juice and cayenne and process until smooth. With the machine on, slowly pour in the 3/4 cup of oil until incorporated. Season with black pepper.
Preheat the oven to 400°. Lightly oil a 9-by-13-inch baking dish and spread the brandade in the dish. Sprinkle the cheese on top. Bake on the top shelf of the oven for 20 minutes, until golden brown. Serve with toasts.
The assembled brandade can be refrigerated for up to 3 days. Bring to room temperature before baking.
Bright, dry Riesling is a good match for rich fish dishes like this gratin.