Place onion in the bottom of the slow cooker; rub the outside of the roast with salt, pepper, and garlic powder. Pour Dr. Pepper over the pork, cook on high 4-5 hrs or on low 7-8 hrs. The meat will be very tender; using 2 forks, shred the pork then place back in the juices. Add barbecue sauce to taste, allow to cook an additional 30-60 minutes if desired.

Serve on choice of bread and choice of sides.
*If your pork produces a lot of juice, you might like to remove some before adding the shredded pork back into the mixture*