- 2/3 cup chopped plum tomatoes
- 1/2 cup shredded part-skim mozzarella cheese
- 1/4 cup chopped kalamata olives
- 1 teaspoon minced garlic
- 2 teaspoons extra-virgin olive oil, divided
- 1/2 teaspoon finely chopped fresh rosemary
- 1/8 teaspoon freshly ground pepper
- 4 portobello mushroom caps, 5 inches wide
- 2 tablespoons lemon juice
- 2 teaspoons reduced-sodium soy sauce
- Combine tomatoes, cheese, olives, garlic, 1 teaspoon oil, rosemary and pepper in a small bowl.
- Preheat grill to medium.
- Discard mushroom stems. Remove brown gills from the undersides of the caps using a spoon; discard gills. Mix the remaining 1 teaspoon oil, lemon juice and soy sauce in a small bowl. Brush the mixture over both sides of the caps.
- Oil a grill rack (see Tip). Place the caps on the rack, stem sides down, cover and grill until soft, about 5 minutes per side. Remove from the grill and fill with the tomato mixture. Return to the grill, cover, and cook until the cheese is melted, about 3 minutes more.