First, create the spice rub by combining the first 7 ingredients. Rub the spice blend all over the pork. Cover + refrigerate for at least 1 hour, or preferably overnight.
Place the spice-rubeed pork in your slow cooker. Pour in the 12 ounces of soda + liquid smoke. Cover + cook on LOW for 8-10 hours, until the pork is very tender. (Note: I’ve made this recipe times, and have found that it’s very forgiving. If it cooks longer than that because you’re cooking it overnight, it’ll still be fantastic).
Remove the pork from the slow cooker + reserve 1/2 cup of the cooking liquid. While the pork is still warm, you want to “pull” the meat: Grab 2 forks. Using 1 to steady the meat, use the other to “pull” shreds of meat off the roast. Put the shredded pork in a bowl (or back in the crock-pot) + pour the 1/4 cup reserved cooking liquid over it. If it looks like it could use some more, pour in the remaining 1/4 cup liquid. Stir it all up well.
NOTE: I prefer my pulled pork served with just a small side of BBQ sauce, not smothered in it, so I just topped with a drizzle of BBQ at this point. If you like yours saucy + smothered in BBQ sauce, you can RETURN the shredded pork to the crock-pot at this point, add in one bottle of your favorite BBQ sauce + continue to cook covered on LOW for 20-30 minutes, until pork is fully hot again.