Veal shanks braised in wine-tomato sauce are a traditional one-pot Milanese comfort dish. A flurry of parsley-lemon gremolata cuts through the meat’s richness for a balanced and beautiful main, fit for a holiday feast.
Osso buco: Preheat oven to 325 degrees F. Tie veal shanks at the equator with kitchen twine. Preheat a heavy-bottomed pot over medium heat. Season veal shanks with salt and pepper on all sides, then evenly dust with flour. Add 1 tablespoon oil to the pot and swirl to evenly heat, 30 seconds. When oil is shimmering, add the veal shanks and sear on both sides until brown, 2–3 minutes per side. Then sear the sides. Meanwhile, prepare the vegetables.
While the veal shanks are browning, prepare the mirepoix: Trim carrots and celery, then cut into a uniform large dice. Peel and halve the onion, then dice into the same size as the carrots and celery. Meanwhile, continue turning the veal shanks so they brown on all sides (turn heat down to low if the pot gets too smoky). The brown bits forming on the bottom of the pan, called "fond," will be used to flavor the sauce later. Smash garlic; remove skin, trim the tip, and slice. Turn off heat, remove browned shanks from pot, and set aside, leaving fond and drippings in the pot.
Turn heat to medium-low. Add butter and all of the vegetables to the pot. Season with salt and stir, scraping up the fond. Sauté until soft, 3-4 minutes. Turn heat to medium and add wine to the vegetable mixture. Stir and scrape to finish deglazing the pot, then reduce by half, 2–3 minutes. Meanwhile, make a bouquet garni by tying the parsley stems and thyme together with twine. (Making a bouquet will make it easier to remove and discard the herbs when the dish is finished.) Add to the pot. Peel three long strips of lemon peel, from top to bottom, and add to the pot, followed by the bay leaves. Stir, then add the beef broth and crushed tomatoes.
Bring sauce to a simmer, and continue simmering until reduced slightly, 6–8 minutes. Nestle the osso buco pieces into the vegetable sauce mixture; it should come halfway up the sides of the veal shanks. Spoon sauce over the tops of the shanks. Cover and place in the oven to braise for a total of 2 hours, checking after 1 hour and basting with sauce. Meanwhile, make the gremolata.
Gremolata: Pick the leaves off the parsley and finely chop. Set aside. Peel strips of lemon peel from top to bottom, trying to avoid the white pith as much as possible. Julienne the peel into long slivers, then finely dice. (Alternatively, you can use a Microplane zester.) Add zest to the parsley mixture. Smash and peel the garlic cloves; finely chop 1½ cloves and add to the bowl. Season to taste with salt, stir, and set aside.
Assembly: After 2 hours of braising, remove osso buco from the oven. Shanks should be fork tender, with sauce clinging to the meat. Taste and adjust seasoning. Transfer shanks to a serving platter and remove the strings. Discard bouquet garni, bay leaves, and lemon peels. Ladle sauce over the shanks, followed by a sprinkling of gremolata. Serve with remaining gremolata on the side.