2 portobella mushrooms, Big Ones!
2 tablespoons extra virgin olive oil
2 tablespoons balsamic vinegar
1 teaspoon fresh thyme, chopped
1/2 teaspoon garlic powder
Kosher salt and freshly ground black pepper to taste
1 large roasted red pepper, peeled, halved lengthwise
Watercress
Thinly sliced red onion
2 round toasted rolls

Heat broiler or grill. Remove stems from mushrooms Clean mushroom caps. Mix oil, vinegar, thyme, garlic powder, salt and pepper in a glass. Brush one side with slightly less than half the oil and vinegar mixture. Put caps under a broiler or on the grill for about 4 minutes. Turn over, brush with all but 1 tablespoon of remaining oil and vinegar mixture. Broil 4 minutes more or until nicely browned and tender. Brush the inside of each bun with remaining oil and vinegar mixture. Top with mushroom cap, then roasted pepper half, then watercress. Add onion rings if desired. a sour cream and horseradish sauce is a very good topping to the sandwich but optional.