Marinate the meat: In a large bowl, combine all the marinade ingredients. Mix well and refrigerate in the bowl or a thick sealable plastic bag for at least 2 hours or up to 1 day. When ready to cook, strain off the marinade and reserve for cooking. Drain meat on paper towels and pat until very dry. Sprinkle with salt and pepper. Place a large, heavy pot with a tight-fitting lid on the stove and rub the bottom with the smashed, peeled clove of garlic, until coated with the garlic’s oils. Discard garlic. Add 2 tablespoons vegetable oil, and cook over medium heat until shimmering. Add half the meat and brown gently on both sides while preparing the vegetables. There’s no need for a hard crust to form; a little browning is all that’s required. When browned, remove meat to paper towels to drain. Repeat with remaining 2 tablespoons oil and meat. Return all the browned, drained meat to the pot. Meanwhile, cut the celery (if using) and carrots into large chunks. Peel and chop the onions. Peel and dice the potato. Heat oven to 250 degrees. In a separate skillet, heat pancetta (if using) and olive oil over low heat. Cook gently until the fat renders. When the pork fat is running, add onions, celery, carrot, onion and minced garlic. (If not using pancetta, simply heat olive oil and add vegetables and garlic.) Cook gently, stirring, until softened and golden, about 10 minutes. Raise the heat, add tomato paste and cook, stirring, until fragrant and sizzling. Add the bouquet garni, reserved marinade and potato. Let bubble fiercely for 5 to 10 minutes, until liquid is thickened and syrupy. Add mixture, once cooked, to the pot with the meat. Pour in the wine and, if needed, enough broth to just cover the ingredients. Stir to combine. Bring to a simmer, cover tightly and bake 4 to 5 hours, until the meat is soft enough to eat with a spoon and the sauce is rich and thick. After 4 hours, if liquid seems thin, uncover pot for the rest of the cooking. When done, let cool slightly, uncovered. Remove and discard celery (if using) and bouquet garni. To thicken the stew, use a fork to mash some of the the carrots and potatoes into the liquid; or, remove and purée them, then add back in. Taste and adjust the seasonings with salt and lots of freshly ground pepper. Reheat and serve immediately, or let cool and refrigerate. Serve within 3 days; the flavor will only improve. Garnish each serving with a sprinkling of chopped thyme and parsley.