Pre-heat oven to 225 degrees F.
Trim excess fat from roast, save trimmimngs
In a dutch oven over med-high heat, heat olive oil
Add onions, garlic, salt, pepper and rosemary sprigs, cook until onions are translucent (about 5 min)
Add cayenne and mustard, cook 1 min more
Add beer and turn off heat
In a heavy skillet over high heat, render fat trimmings and discard chunks
Sear roast on all sides in pork fat until a golden brown crust forms on the meat (about 5 min per side)
Place seared roast in dutch oven with beer/onion mixture
Pour moasses over meat and let sit a few moments to allow sugars to seep into the meat
Add vinegar and enough stock to just cover the roast
Place in 225 degree oven for 8 to 12 hours.
Remove from liquid and let stand on wwire rack to drain until cool enough to work with. Scape off any excess fat and shred with two forks
Mix with your favorite BBQ sauce and ENJOY!
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