Osso Buco Halibut with Gremolata
2 tablespoons olive oil
1/2 medium onion, chopped
3/4 cup chopped celery
3/4 cup chopped peeled carrot
2 garlic cloves, minced
1 tablespoon tomato paste
1 cup white wine
4 cups chicken stock or canned low-salt chicken broth
115-ounce can diced tomatoes, drained and chopped fine
1/2 cup orange juice
1/3 cup chopped lemongrass
1/4 cup soy sauce
4 fresh thyme sprigs
1 bay leaf
6 5-ounce halibut fillets
1/4 cup balsamic vinegar
2 tablespoons (1/4 stick) unsalted butter, room temperature
1/4 cup finely chopped fresh parsley
3 garlic cloves, finely chopped
Heat 1 olive oil in large saucepan over medium-high heat. Add onion, celery, carrot and garlic; sauté until brown, about 10 minutes. Add tomato paste and cook 2 minutes. Add white wine and simmer until liquid is reduced by half, scraping up browned bits, about 5 minutes. Add next 7 ingredients; simmer until mixture is reduced to 3 cups, about 50 minutes. Discard bay leaf. Season sauce with salt and pepper.
Preheat oven to 350°F. Sprinkle halibut with salt, pepper and cayenne pepper. Heat olive oil in large skillet over high heat. Add fish to skillet and cook until brown, about 2 minutes per side. Transfer fish to plate. Pour off oil from skillet. Reduce heat to low. Add balsamic vinegar to skillet; simmer 1 minute. Add sauce. Whisk in butter. Season with salt and pepper. Pour sauce into 13x9x2-inch glass baking dish. Place fish atop sauce in dish. Bake until fish is opaque in center, about 10 minutes.
To make the Gremolata topping, remove peel in long strips from lemon. Mince lemon peel. Transfer to small bowl. Mix in parsley and garlic. Sprinkle over the halibut and sauce and serve with whipped potatoes.