Lamb Osso Buco Slow-Cooked

Put flour into a shallow wide bowl. Season lamb shanks with salt and pepper; dredge through flour until coated, shaking off any excess flour.

Heat a large skillet over medium heat; add butter and heat until foaming. Cook lamb shanks in hot butter until golden, about 5 minutes per side. Transfer lamb shanks to a slow cooker.

Pour wine into the skillet and bring to a boil while scraping the browned bits of food off of the bottom of the pan with a wooden spoon; transfer to the slow cooker. Add tomatoes with their juice, onion, chicken broth, celery, and thyme leaves to the slow cooker.