Portabella And Provolone

• 1/4 cup olive oil
• 3 tablespoons balsamic vinegar
• salt
• fresh ground black pepper
• 8 large portabella mushrooms (6 to 8 ounces each)
• 8 ounces sharp provolone cheese, coarsely grated
• 2 ounces aged asiago cheese, finely grated
• 2 teaspoons fiinely chopped fresh oregano (or 1/2 t. dried)
• 4 slices beefsteak tomatoes (1/4-inch thick)

1. Preheat oven to 400u0b0.
2. In a small bowl, whisk the oil, vinegar, salt, and pepper together; set aside.
3. Moisten a paper towel and wipe the mushrooms to remove dirt.
4. Cut out the stems and the gills; place the mushrooms in a glass dish, round side up; pour the oil mixture over the mushrooms, rubbing it in with your fingers; turn the mushrooms and lightly sprinkle the insides with salt and pepper; marinate for 10 minutes.
5. Remove the mushrooms from the marinade and place on a baking sheet, rounded side up.
6. Bake 10-12 minutes or until they begin to brown and shrink a bit.
7. Turn the mushrooms and bake 10-12 minutes, or until some of the liquid has surfaced and the mushrooms have browned further.
8. Remove from oven; let sit until cool enough to handle.
9. Mix the cheeses and oregano together in a bowl.
10. Scatter 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.
11. Heat a large nonstick skillet over medium heat for 2 minutes; put the mushroom sandwiches in the skillet (in batches if needed), cover, and cook 3-5 minutes, or until the undersides are dark brown and the cheese has begun to melt.
12. Uncover, and turn the mushroom sandwiches, pressing firmly with a spatula to flatten them slightly.
13. Cover and cook 2-3 minutes or until the undersides have turned a shade or two darker and the cheese has melted completely; let cool slightly and cut in half; serve.

olive oil, balsamic vinegar, salt, fresh ground black pepper, portabella mushrooms, provolone cheese, cheese, fresh oregano, tomatoes

Taken from www.food.com/recipe/portabella-and-provolone-180138 (may not work)