Creating delicious Balsamic Grilled Portobello Mushrooms is simple if you follow these steps:

1. Clean the Mushrooms: Gently clean the Portobello mushrooms with a damp paper towel to remove any dirt.
2. Prepare the Marinade: In a small bowl, whisk together balsamic vinegar, olive oil, minced garlic, oregano, salt, and black pepper.
3. Marinate the Mushrooms: Place the cleaned mushrooms in a shallow dish or resealable bag. Pour the marinade over them and ensure they are fully coated. Allow them to marinate for at least 30 minutes.
4. Preheat the Grill: Preheat your grill to medium-high heat, ensuring the grates are clean and well-oiled to prevent sticking.
5. Grill the Mushrooms: Remove the mushrooms from the marinade and place them gill-side down on the grill. Cook for about 5 to 7 minutes before flipping.
6. Finish Cooking: Flip the mushrooms and grill for another 5 to 7 minutes or until they become tender and have grill marks.
7. Serve: Remove from the grill and plate them. If desired, garnish with fresh parsley for additional color and flavor.

These straightforward steps will lead you to a delicious dish that everyone will appreciate.