Slice white onion and lay on the bottom of crock pot. Mix together paprika, salt, red pepper, garlic powder. Rub on the pork loin and place on top of the onion.
Mix together coleslaw and dressing and let sit.
Add a beer to the crock pot and cook on low for 8 – 10 hours, or until pork is done and pulls apart. Serve on mini Hawaiian rolls with coleslaw.