Pour 1 can of root beer in the bottom of your slow cooker. Place the pork in your slow cooker in root beer (if the meat is too big for your slow cooker you can cut it into pieces). Cook on low about 8-10 hours or until pork is very tender. Discard liquid from slow cooker and pull pork apart with 2 forks until shredded.
While pork is cooking, prepare BBQ sauce. Place tomatoes, tomato paste, and onion in blender (or food processor) and process until smooth. Pour into large saucepan over medium-high heat. Add vinegar, 2 cans root beer, brown sugar, molasses, liquid smoke, salt, garlic powder, black pepper, and chipotle to pan and whisk to combine.
Bring sauce to a boil, reduce heat to simmer, and cook about 1 hour or until thickened and reduced, stirring occasionally. Refrigerate sauce for a few hours or until ready to serve.
To serve, combine desired amount of BBQ sauce with pork and serve. Serve with rolls and coleslaw if desired.
SNAPPY TIPS: Make sure you buy a piece of pork that will fit in your size slow cooker. I would suggest buying the biggest piece that will fit. You can cut the meat into chunks if it won’t fit in as one piece. Pulled pork in BBQ sauce freezes great, so make a big batch! The BBQ sauce also freezes well so whatever you don’t use can be frozen in a small container. If you would like the root beer flavor to be more pronounced add a little root beer extract.SNAPPY SUBSTITUTIONS: You may have to alter the ingredients in the BBQ sauce a little for your family’s personal taste. You can add more/less chipotle to adjust the spiciness and more/less sugar or molasses to change the sweetness. White vinegar can be substituted for the apple cider vinegar.