This is another recipe that I dug up from last year from Cooking Light. It's great as a side dish to steak or even an appetizer. I ended up just eating a couple of these for a meal...
-4 (5-inch) portobello mushroom caps
-2/3 cup chopped plum tomatoes
-1/4 cup shredded mozzarella cheese
-1 tsp olive oil, divided
-1/2 tsp finely chopped fresh (or a less dried) rosemary
-1/8 tsp coarsely ground black pepper
-2 tsp low-sodium soy sauce
-2 tsp minced fresh or dried parsley
Preheat the grill on medium-high.
First, wipe you mushroom caps with a damp paper towel to remove excess dirt. You don't want to rinse or wash your mushrooms. If you do, they will absorb the water and become soggy. Remove the stem and gills with a knife and/or spoon and discard.
Next, in a small bowl combine 1/2 teaspoon olive oil, lemon juice and soy sauce. Using a marinade or kitchen brush, brush this mixture onto both sides of the mushroom caps.
In another bowl combine chopped tomatoes, cheese, 1/2 tsp olive oil, rosemary, pepper and garlic. Mix together.
Coat your grill with cooking spray. Place the mushroom caps on the grill, stem-side down. Grill for about 5 minutes on each side. Add 1/4 of the tomato mixture to each cap and grill for another 3 minutes until the cheese is melted. You'll notice mine are a bit "over-stuffed" because I only used 2 caps instead of four.
Remove from the grill and serve hot!