1 Whole pork tenderloin
1 onion chopped
4 or 5 garlic cloves minced
1/2 c soy sauce
1/2 c worchestershire
1 bottle of Leghumper porter(or any stout/porter)
Marinate for 24 hrs, then start your coals. Push coals to the outside to cook so you have indirect heat. Throw the tenderloin on the grill. Cooking time will depend on size.
Take the marinade in a skillet and reduce till decently thick, take half and mop your tenderloin on the grill and save the rest for after you have sliced the tenderloins into medallions, drizzle on top.
NOTE: No actual measurements were taken so this is a guess.