6 fresh portobello mushrooms (about 1 1/2 pounds), stems trimmed

For the marinade:

6 tablespoons balsamic vinegar

3 garlic cloves, minced

2 shallots, minced

1 cup plus 2 tablespoons olive oil

salt and freshly ground black pepper

For the sandwich:

6 round country sour dough rolls, sliced in half

1 1/2 cups crumbled goat cheese

24 marinated sun-dried tomato slices

18 basil leaves

1. Trim the mushroom stems. Remove the black gills on the underside of the mushroom cap by scraping with the edge of a teaspoon. The gills need to be removed so their dark color and juices will not leach into the sandwich. Set aside.

2. In a small bowl, whisk together the balsamic vinegar, garlic, shallots, olive oil, salt and pepper. Arrange mushroom caps in a single layer in a shallow, nonaluminum dish and pour 1/2 of the marinade (reserve the rest) over mushrooms. Cover and marinate 1 hour, turning after 1/2 an hour.

3. Heat a lightly oiled grill or grill pan. Remove mushrooms from marinade, place on the hot grill and use a skillet or weight to press down on mushrooms. Sear mushrooms 2 minutes on each side, or until tender. Reserve.

4. Drizzle a tablespoon of reserved dressing on each bread half. Place the mushroom on top of the bread bottom. Layer the goat cheese, sun-dried tomatoes and basil leaves on the other half. Place the halves together. Cut the sandwich in half, wrap in a sandwich bag or foil until serving.

(Diane Rossen Worthington is an authority on new American cooking. She is the author of 18 cookbooks, including “Seriously Simple Parties,” and a James Beard Award-winning radio show host. You can contact her at www.seriouslysimple.com.)