Ingredients For the sauce:
1 cup seafood stock or clam juice
1 cup heavy cream
1/2 cup plus 3 tablespoons good white wine, such as Chablis, divided
3 tablespoons tomato puree
1/2 teaspoon saffron threads
8 ounces raw shrimp, peeled, deveined, and cut in half crosswise
8 ounces raw halibut, cut into1-inch chunks
8 ounces cooked lobster meat, cut into 1-inch chunks
7 tablespoons unsalted butter, divided
1 tablespoon all-purpose flour
Kosher salt
Freshly ground black pepper
3 cups julienned leeks, white and light green parts (2 large)
1 1/2 cups julienned carrots (3 carrots)
1 cup Panko (Japanese dried bread crumbs)
1/3 cup freshly grated Parmesan
2 tablespoons minced fresh flat-leaf parsley
1 tablespoon chopped fresh tarragon leaves
1 tablespoon minced garlic (2 cloves)
Preheat the oven to 375 degrees F. Place 4 individual gratin dishes on sheet pans. (If the recipe is doubled, serve it in a 14 by 9 1/4-inch oval gratin dish.)
Steps For the sauce:
Combine the stock, cream, 1/2 cup of the wine, tomato puree, and saffron in a medium saucepan. Bring to a boil, lower the heat, and add the shrimp. After 3 minutes, remove the shrimp from a bowl with a slotted spoon. Add the halibut to the stock for 3 minutes, until just cooked through, and remove to the same bowl. Add the cooked lobster to the bowl.
Continue to cook the sauce until reduced by half, about 12 minutes. Mash 1 tablespoon of the butter together with the flour. Whisk the butter mixture into the sauce along with one teaspoon salt and 1/2 teaspoon pepper. Simmer, stirring constantly, until thickened, about 5 minutes. Set aside.
Melt 3 tablespoons of the butter in a medium saute pan. Add the leeks and carrots and cook over medium heat for 5 minutes, until softened. Add the remaining 3 tablespoons of wine, 1/2 teaspoon salt, and 1/4 teaspoon pepper and cook for 5 to 10 minutes, until tender. Set aside.
Combine the panko, Parmesan, parsley, tarragon, and garlic. Mix the remaining 3 tablespoons of butter into the crumbs until they’re moistened.
Divide the seafood among the 4 gratin dishes. Strew the vegetables on top of each dish. Pour the sauce equally over the seafood and vegetables and spoon the crumbs evenly on top. Bake for 20 minutes, until the top is browned and the sauce is bubbly. Serve hot.