GARNISH: Trim stems of mushrooms to within 1/2" of caps. Wash and drain
mushrooms and slice 1/4" thick. Over high heat, melt 2 tablespoons
butter. When it sizzles, reduce heat to medium, add mushrooms and saute
until golden and soft. Stir meat extract or beef concentrate into pan
juices. Taste, season with salt and pepper and sprinkle with chopped
chives.
BASTING: Crush garlic and minced onion in a garlic press. Blend together garlic and onion, Worcestershire sauce, salt, freshly ground pepper and very soft butter (6 tablespoons).
STEAKS: Preheat oven to 550 degrees for 1/2 hour. Trim fat and tail from
Porterhouse steaks weighing 10 pounds altogether. Place steaks in
shallow baking pan and brush with 1/2 of basting mixture. Bake 12
minutes, then turn steaks and insert meat thermometer into one of them.
Brush second sides with rest of basting mixture. Bake to temperature
recommended for rare (130-140 degrees) or medium rare (160 degrees).
Remove steaks to heated serving platter. With a perforated spoon, heap
mushrooms on steaks, reserving juice. Place baking pan over high heat
on top of stove. De-glaze drippings with 1/4 cup hot water and add
mushroom juice and 1 tablespoon butter. Taste; correct seasoning and
pour sauce over steaks. Have plenty of French bread for dunking.
Serves 10 to 12