In a large skillet set to medium-high heat, add the cooking oil. When the oil is hot, brown the pork shoulder on all sides.
Add the onion down in the slow cooker. Add the browned pork on top of the onions.
Sprinkle over the salt, pepper, cayenne pepper, onion powder, garlic powder, oregano,
and celery salt.
Add the liquid smoke, and chicken broth (or water) around the pork.
Cover and cook on high for 7 hours or low for 10.
When the cooking time is done, remove the pork on to a plate, shred with two forks and discard fat.
Preheat oven to 425°
Add meat to each bun bottom and top with the Sargento® Cheese, I use 2 slices per sandwich. Add the tops to the sandwiches. Wrap each sandwich in foil. Place the wrapped sandwiches on a cookie sheet. Place in oven for 20 minutes, or until the cheese had melted and the bun is toasty. Serve and enjoy!