Stuffed portobello mushrooms

Pulling out our grill for some fun, summertime grilling presented a challenge for me.  What to grill for a vegetarian meal?  The obvious for carnivores are steaks, burgers and chicken.  For a vegetarian though?  We need to get creative....
Portobello mushrooms are usually the most obvious ingredients, since they are both meaty and hardy and will hold up to the fire. 
Here is my stuffed portobello mushroom recipe that I have adapted:

2 portbello mushrooms - stems and gills removed
1/4 cup kalamata olives - chopped
2 roma tomatoes - chopped
1 clove garlic - minced
1/4 cup - shredded mozzarella
2 tbls basil - minced

Combine all ingredients in a bowl. 

Grill the portobello mushrooms on both sides and then stuff with mixture and grill for about 5 more minutes.
Remove from grill and enjoy!