Try this one guys;

1 Tbsp garlic, minced
2 tsp fresh rosemary, minced
2 Tbsp olive oil
2 Tbsp balsamic vinegar
2 portabello mushrooms

Mix all ingredients except mushrooms. Brush mixture on both sides of mushrooms. Cover and refrigerate 30 min.
Cook on low preheated grill or in oven on lower rack 5 minutes on each side. Serve immediately. Yummy:D
86 calories, 6gm fat, 6gm carbohydrates, 2gm fiber.