Portobello and Provolone

1/4 cup olive oil
3 tablespoons balsamic vinegar
salt and freshly ground pepper
8 large portobello mushrooms (6-8 ounces each)
8 ounces sharp Provolone cheese, coarsely grated
2 ounces aged Asiago cheese, finely grated
2 teaspoons finely chopped fresh oregano (or 1/2 teaspoon dried)
4 slices beefsteak tomato (1/4 inch thick)

Preheat the oven to 400 degrees Fahrenheit.

In a small bowl, whisk together the oil, vinegar and salt and pepper to taste. Set aside.

To prepare the mushrooms: Moisten a paper towel and wipe the mushrooms to remove dirt. Cut out the stems and the gills. Place mushrooms in a glass dish, round side up, and pour the oil mixture over them, rubbing it in with your fingers. Turn the mushrooms and lightly sprinkle the insides with salt and pepper. Marinate for 10 minutes.

To precook the mushrooms for all methods: Remove the mushrooms from marinade and place on a baking sheet, rounded side up.

Bake for 10 to 12 minutes, or until they begin to brown and shrink a bit. Turn the mushrooms and bake for 10 to 12 minutes, or until some of the liquid has surfaced and the mushrooms have browned further. Remove from the oven and let sit until cool enough to handle.

To assemble: In a small bowl, mix the cheeses and oregano. Distribute the cheese mixture evenly over the inside of 4 mushroom caps, followed by a tomato slice. Sprinkle with salt and pepper to taste, and place the remaining 4 mushroom caps on top, rounded side up.

Stovetop method:
Heat a large nonstick skillet over medium heat for 2 minutes. Put the mushrooms in the skillet (in batches if necessary), cover and cook for 3 to 5 minutes, or until the undersides are dark brown and the cheese had begun to melt. Uncover, and turn the mushrooms, pressing very firmly with a spatula to flatten them slightly. Cover and cook for 2 to 3 minutes or until the undersides have turned a shade or two darker and the cheese has melted completely. Let cool slightly, cut in half, and serve.

Sandwich maker method: Preheat the sandwich maker (if your machine has adjustable heat, set it to medium). Follow directions for sandwich assembly, and cook until the grill marks are dark and the cheese has melted completely. Let cool slightly, cut in half, and serve.

Gas grill method:
Brush the grill rack with oil and preheat the grill to medium. Follow directions for sandwich assembly. Grill the mushrooms for 3 to 5 minutes, or until the cheese has begun to melt (gently lift the top off one of the mushrooms to check). Turn the mushrooms with a spatula, pressing firmly to flatten them slightly, and cook 2 minutes more, or until the mushrooms are dark brown and the cheese has melted completely. Let cool slightly before serving.

Servings: 4
By Laura Werlin Author of A Great Grilled Cheese: 50 Innovative Recipes for Stove Top, Grill, and Sandwich Maker
Source: American Dairy Association