Portobello mushrooms are delicious baked or grilled, whole or sliced. They make an excellent meat substitute and are a hearty addition to stir-fry dishes and sauces. When grilling or broiling, lightly brush caps and stems with oil to keep them moist, and season to taste. Grill or broil 4 to 6 inches (10 to 15cm) from heat source for four to six minutes on each side, brushing with oil again once or twice during cooking. The stems are very woody and should be removed and saved for soups and stocks.