North Carolina Style Pulled Pork Sandwiches

2 tsp salt
1 tsp garlic powder
1 tsp pepper
1 pork shoulder (5 pounds), patted dry
2 cups apple cider vinegar
2/3 cup of ketchup
2 tbsp dark brown sugar
2 tbsp Worcestershire sauce
1 tbsp ground mustard
1 tbsp chili powder
1/4 tsp cayenne pepper
Hamburger buns

Combine the salt, garlic powder, and pepper in a small bowl.
Rub the spice mixture over the pork and set aside.
In a small saucepan, combine the vinegar, ketchup, brown sugar, Worcestershire sauce, ground mustard, chili powder, and cayenne pepper. Simmer over low heat for 5 minutes, stirring occasionally. 
Place the pork in the crock pot, and pour 2/3 of the sauce over it.
Cook on high for 4-5 hours, until the pork is tender and fully cooked.
Place the pork on a wire rack on top of a baking sheet with a lip, until cool enough to handle. 
Shred the pork, and place in a large bowl. 
Pour the remaining sauce over the shredded pork, and stir.
Toast the hamburger buns, top with the shredded pork, and enjoy!