Braised for hours in a slow cooker, these lamb shanks are falling-off-the-bone tender so serve with a spoon to enjoy all the flavors of the lamb, vegetables and sauce.
Put the onion, celery, carrots, garlic, stock, tomatoes, tomato paste, thyme and bay leaf in a slow cooker and stir to combine.
Season the lamb shanks with salt and pepper. In a large sauté pan over medium-high heat, warm the olive oil until nearly smoking. Add the shanks and brown on all sides, about 5 minutes total then transfer the shanks to the slow cooker.
Remove the sauté pan from the heat, pour in the wine and return to medium-high heat. Bring to a simmer while deglazing the pan to remove and dissolve the browned residue from the pan which will add to the flavor of the sauce. Add the deglazed pan mixture to the slow cooker, cover and cook on high for at least 6 hours. Transfer the lamb shanks to a large serving dish.
Remove the bay leaf from the cooking liquid. Use a blender to puree the remaining liquids and solids until smooth. Pour the sauce over the shanks and serve over mashed potato with an Embrace Grenache.