Pork Spiedini

2 pounds boneless pork loin, cut into 3/4-inch cubes
3/4 cup cider vinegar
3/4 cup olive oil
4 tablespoons lemon juice
1 tablespoon Worcestershire sauce
1 tablespoon dried oregano
2 cloves garlic, minced
2 teaspoons black pepper
1 teaspoon salt
1/2 teaspoon cayenne
6 slices thick Italian bread

Mix together all ingredients except bread, place in a self-sealing plastic bag and refrigerate 4 to 24 hours.
Remove pork cubes from marinade (discarding remaining marinade); thread pork onto skewers*.
Grill over hot coals for 4 to 5 minutes; turn and grill another 4 minutes.
Serve by pulling meat off of skewer onto Italian bread.
Serves 6.

* If using bamboo skewers, soak in water for 30 minutes to prevent burning.

Source: http://www.cooksrecipes.com/pork/pork_spiedini_recipe.html