Ingredients
4 tablespoons unsalted butter, room temperature
2 medium carrots, peeled and finely chopped
1 stalk celery, finely chopped
2 shallots, minced (1/4 cup)
5 sprigs thyme
Coarse salt and freshly ground pepper
1 can (14.5 ounces) whole peeled plum tomatoes in juice
16 ounces clam juice
1 1/2 pounds skinless cod or halibut fillet, cut into 1 1/2-inch pieces
4 slices baguette, each 1 1/2 inches thick on the diagonal
Preparation
Heat broiler with rack 8 inches from heating element. Melt 2 tablespoons butter in a large ovenproof skillet over medium-high heat. Add carrots, celery, 3 tablespoons shallot, and 3 thyme sprigs; season with salt. Cook, stirring occasionally, until vegetables are golden in spots, about 5 minutes. Stir in tomatoes and juice; simmer, breaking up tomatoes into bite-size pieces, until liquid is mostly evaporated, about 5 minutes. Stir in clam juice and fish; return to a simmer. Remove from heat.
Spread remaining 2 tablespoons butter over bread. Sprinkle with remaining 1 tablespoon shallot and thyme leaves from 2 sprigs; season with salt and pepper. Place atop fish. Broil until fish is just cooked through and bread is toasted, about 2 minutes (if bread is darkening too quickly, move skillet to lower rack); serve.
