- Place the beans in large bowl. Cover with warm water and let soak overnight at room temperature. Add water, as needed, so that the beans are always well covered. Rinse and drain.
- With the rack in the middle position, preheat the oven to 180 °C (350 °F).
- In a large ovenproof pan, brown the lamb shanks in the oil. Season with salt and pepper. Set aside on a plate.
- In the same pan, brown the onions for about 2 minutes. Add oil, as needed. Add the garlic and cook 1 minute. Return the shanks to the pan and add the beans, tomatoes, broth, beer, molasses, bacon, and bay leaf. Lightly season with salt and pepper. Bring to boil and bake, covered, for about 2 hours.
- Add the vegetables and cook, covered, for about 1 hour and 30 minutes or until the beans and shanks are tender. Adjust the seasoning.