1 pound veal sweetbreads
? cup lemon juice
1 teaspoon Worcestershire sauce
1 teaspoon salt
? teaspoon pepper
? teaspoon dry mustard
12 bacon slices, halved
� cup melted butter or margarine
4 10-inch skewers
Simmer the sweetbreads in boiling salted water, covered, for 25 minutes. Drain and place in cold water; remove the membranes and veins. Cut them into 24 pieces, cover and refrigerate for several hours or overnight.
Remove stems from the mushrooms. Place the mushroom caps in a mixing bowl; combine the lemon juice, Worcestershire, salt, pepper and mustard. Pour over the mushroom caps and refrigerate several hours or overnight, tossing occasionally.
Line the firebox with broiling foil; let the coals burn down until they are covered with gray ash.
Roll up the bacon pieces and string on the skewers, alternating them with the sweetbread pieces and mushroom caps. Brush with melted butter; grill 15 to 20 minutes, turning often and brushing with butter. When the sweetbreads are golden and the mushrooms are done, place on a warm platter, pour the remaining butter over all and sprinkle with parsley. The recipe will provide four servings.