Osso Buco with Tomatoes, Olives, and Gremolata

Preheat oven to 325°F.

Pat shanks dry and season with salt and pepper. Divide shanks and flour between 2 large sealable plastic bags and shake to coat, then remove shanks from bags, shaking off excess flour.

Heat oil and 2 tablespoons butter in ovenproof pot over moderately high heat until foam subsides, then brown shanks well in 2 batches, 10 to 12 minutes per batch, transferring to a plate.

Reduce heat to moderate and add remaining tablespoon butter to pot along with onions, carrot, celery, and garlic and cook, stirring, until onions are pale golden, about 5 minutes.

Add remaining stew ingredients and bring to a boil, stirring. Arrange shanks in pot in 1 layer and return to a simmer. Cover pot and braise shanks in middle of oven until very tender, about 2 1/2 hours.

Remove strings from osso buco and discard along with parsley sprigs and bay leaf.

Stir together gremolata ingredients in a small bowl and sprinkle over osso buco.

Serve immediately.

• Osso buco (without gremolata) can be made 1 day ahead. Cool completely, uncovered, then chill, covered. Reheat, covered, in a 325°F oven 30 to 40 minutes. • Osso buco can also be cooked in a large roasting pan. Straddle pan across 2 burners for browning and boiling, then cover pan tightly with foil for braising.