1/2 cup balsamic vinegar
1/2 cup distilled white vinegar
2 tablespoons lemon juice
2 tablespoons Worcestershire sauce
2 tablespoons ketchup
2 tablespoons soy sauce
1/2 teaspoon ground black pepper
1/4 teaspoon salt
3 cups beef broth
1 (5 ounce) can sliced mushrooms, drained
In a large bowl, blend the vinegar, vinegar, lemon juice, Worcestershire sauce, ketchup, soy sauce, black pepper, salt and beef broth. Add enough of the broth to cover completely. Mix well.
Shape mixture into a loaf shape, wrap and chill in the refrigerator or freezer up to 2 hours.
Preheat grill for high heat.
Dip pork into the marinade mixture, then place on the griddle. Cook over medium high heat just until pink spots emerge.
Remove pork from grill; brush with some of the remaining lemon marinade mixture imbedded into the bottom of the pan.
Grill the meat on all sides under high heat for about 30 minutes in the preheated oven.
Return the meat to the pan. Add mushrooms. Fry and sauce over medium heat for about 5 minutes.