Spicy Dr. Pepper Shredded Pork

I got this off of tastykitchen.com

1 whole lg onion
1 whole pork shoulder roast (pork butt) - 5 to 7 lbs
salt and freshly ground black pepper
1 can (11 oz) chipotle peppers in adobo sauce
2 cans dr. pepper
2 tbsp brown sugar

preheat oven to 300 degrees.  Peel onion adn cut into wedges.  lay them in the bottom of a lg. dutch oven.  generously salt and pepper the roast, then set it on top of the onions in the pan.  Pour the can of chipotle peppers over the pork (include the sauce).  Add both cans of dr. pepper.  Add brown susgar to the juice and stir in.  Place lid tightly on pot, then set in oven.  Cook for at least 6 hours, turning the roast 2 or 3 times during the cooking process.  Check meat after 6 hours, it should be falling apart.  If it's not falling apart return to the oven for another hour.  Remove meat from pot and place on cutting board or other work surface.  Use 2 forks to shred the meat, discarding large pieces of fat.  Strain as much of the fat off the top of the juice as you can and discard it.  Return shredded meat to the juice and keep warm until ready to serve.
Enjoy!!