Have a large Dutch oven or stoneware pot on hand for cooking. Preheat oven to 325°F.

1. Rub all surfaces of the pork shoulder with salt and pepper. Wrap with plastic wrap and set in the refrigerator 6–24 hours.

   NOTE: While this step is optional, the seasoning permeates the meat and makes each bite distinctly flavorful.

2. Remove pork from the refrigerator. Using clean hands, rub the liquid smoke over all surfaces of the meat. Let pork sit and come to room temperature, about 20 minutes.
3. Pour the oil into the Dutch oven and set over medium-high heat until just before it begins smoking.
4. Sear the meat on all surfaces.
5. Remove and set aside.
6. Deglaze the pan with 1/4 cup cola. Scrape well to release all of the bits of meat and flavor.
7. Add the onions and cook until slightly softened, about 3–4 minutes. Adjust the heat accordingly and stir occasionally to prevent burning.
8. Stir the garlic cloves into the onion mixture.
9. Set pork on top of the onions and garlic, pouring remaining cola on top.
10. Evenly spread the chipotle peppers in adobo sauce on top of the meat.
11. Cover with tight-fitting lid and bring to a boil. 
12. Remove cookware from the stovetop and set on the middle oven rack of a preheated oven. Cook for approximately 3–3 1/2 hours or until meat is tender and falling apart.
13. Remove from the oven and shred the meat with a fork. Add the salt and mix well. Adjust seasonings to taste and serve.