This sounds like a lot of work but is a very special taste treat.

SAUCE
1 ½ c. vinegar
10 T. tomato catsup
½ t. cayenne pepper
salt and  pepper to taste
1 T. sugar
pinch of hot red pepper flakes
½ c. water
Bring to simmer until sugar melts.  Set aside.

PORK LOIN
2 ¼ lbs boneless pork loin seasoned with salt and pepper
Pre-heat oven to 500 degrees.  Bake 10 minutes.  Reduce heat to 275 and bake 5 hours.  Place meat on grill away from heat with hickory or oak chips to smoke 10 minutes.  Chop meat and serve with above sauce