The meaty texture of portobello mushrooms makes this a great vegetarian dinner to grill up in the summer! Give it a try next time you fire up your BBQ.
Remove the gills and stem from the mushrooms. Turn them over so the stem is facing up. Peel the stem out, and use a spoon to scrape off the black gills on the underside of the mushroom. Be careful not to break the mushroom.
Combine the balsamic, soy sauce, rosemary, garlic powder, and pepper together in a bowl.
Add the mushrooms and turn to coat with the marinade.
Preheat the barbecue or grill pan on medium heat. Grill the mushrooms for about 3 to 5 minutes per side. Brush with the leftover marinade as they cook.
Top with parsley and sesame seeds or serve as a burger with a bun and your favourite burger toppings.