Salt shanks and set aside. In a shallow pot with a lid (a Dutch oven will do), put spices and herbs in with the wine and molasses. If your bacon had the rind on it, put that in, too. Turn the heat to medium-low. Preheat the oven to 300°F.
Pour olive oil into a second pan set over medium heat. Fry the bacon slowly, turning all sides to get crispy. As each piece crispifies, toss it into the pot with the wine. Do not let the wine pot go past a gentle simmer. When the bacon is done, brown the shanks on all sides except the one with the bone; this helps the shank stay together after long cooking. Take your time on this one, and do this over medium heat. It could take 20 minutes. Move the shanks to the wine pot, bone side sticking up.
Put the onions in the other pan and turn the heat up to high. Toss to combine. You will notice the onions will deglaze the pan. After about 5 minutes like this, add the garlic and toss to combine. Continue cooking until you hear the sound change: That’s onions losing enough moisture to begin browning. Cook another minute or two.
Pour in the stock and mix it well with the onions. Bring to a furious boil and make sure you’scraped everything off the bottom of the pan. Add to the wine pot, mixing in with all the other ingredients. Make sure the shanks are still bone side up. Cover and cook in the oven for 3 to 4 hours. Venison, being wild, is difficult to gauge doneness — you might have shot an old deer, or a yearling. Each will require different cooking times.
When the meat is almost falling off the bone, remove it gently and tent it with foil. Fish out the bay leaves, cinnamon stick and as many cloves, peppercorns, allspice and juniper berries as you can in a few minutes. It’s OK if you don’t get them all.
Puree the sauce in a blender or pass it through a food mill set on a medium setting. It should be thick. Pour over the shanks and serve at once with mashed root veggies and something green.