Preheat oven to 325°F.

Tie the veal shanks vertically with kitchen string so the meat will not fall away from the bone during cooking time. (No need to tie the foreshank pieces, if using.) Season with salt and pepper, then toss liberally with the flour, and dust off the excess.

In a large sauté pan, melt the butter and heat the oil over medium heat. In uncrowded batches, brown the shanks on both sides for about 8 to 10 minutes. Transfer to a large ovenproof casserole.

Add the onions, carrots, and celery to the sauté pan and sauté for about 10 minutes, allowing them to brown slightly. Transfer the vegetables to the casserole. Deglaze the pan with the wine, scraping up the browned bits that have adhered to the pan.

Add the tomatoes and broth and bring to a simmer. Pour into the casserole and add the garlic, bay leaves, and parsley. Cover and bake for 1½ hours, or when the shanks are fork tender.

Prepare the gremolata: In a small bowl, combine all the ingredients, cover, and set aside. Remove the shanks from the casserole. Degrease the cooking liquid and season with salt and pepper. Stir in 1 tablespoon of the gremolata.

Cut away the string from the shanks and divide the meat among 6 warm dinner plates. Spoon on some of the sauce and sprinkle with the remaining gremolata.