Slow-Cooked Pork Shoulder

1 lean boneless pork shoulder
1 medium onion, diced
2 tablespoons fresh sage, chopped
2 tablespoons fresh rosemary, chopped
10 cloves garlic, sliced
1 1/2 tablespoons salt
1 tablespoon ground black pepper
1 tablespoon dry white wine
1 tablespoon extra-virgin olive oil
1 tablespoon teriyaki sauce
1/4 cup brown sugar

Preheat oven to 250 degrees. Place the sage, garlic, rosemary, ground pepper, salt, teriyaki sauce and brown sugar in a food mixer, and blend together until thick. While the mixer is still on, the add in the olive oil and white wine. Trim the fat off of the pork roast. Make several holes in the roast 1 inch deep. Place the mixed sauce into each hole and cover the roast with the rest. Cook with onions for 5 hours.