Make the osso buco

• Arrange an oven rack in the bottom third of the oven and heat the oven to 325ºF.
• Place ¼ cup all-purpose flour in a shallow bowl or pie plate. Pat 4 veal shanks dry with paper towels. Season all over with 1 ½ teaspoons of the kosher salt and ½ teaspoon black pepper. Dredge all over in the flour and shake off any excess.
• Heat 2 tablespoons of the olive oil in a large Dutch oven or oven-safe heavy-bottomed pot over medium-high heat until shimmering. Working in 2 batches, add the veal shanks and sear until 2 sides are browned, 4 to 5 minutes per side. Transfer to a plate (they will not be cooked through).
• Reduce the heat to medium. Add the remaining 2 tablespoons olive oil to the pot and heat until shimmering. Add 1 finely diced medium yellow onion, 1 medium peeled and finely diced carrot, 1 medium finely diced celery stalk, and the remaining ½ teaspoon kosher salt. Cook, stirring occasionally, until softened, 7 to 10 minutes.
• Stir in 2 finely grated garlic cloves and 2 tablespoons tomato paste. Cook, stirring occasionally, until the tomato paste is darkened in color, about 2 minutes. Stir in 1 cup dry white wine, 1 cup low-sodium chicken broth, 4 fresh thyme sprigs, and 2 dried bay leaves. Bring to a simmer. Return the veal shanks to the pot in a single layer.
• Cover, transfer to the oven, and bake until the meat is falling off the bone and very tender, about 1 ½ hours (this is a good time to make the gremolata). Remove and discard the bay leaves and thyme stems. Taste and season with more kosher salt as needed.