Wash and cut slight slits on the top side of your mushroom caps, spaced ½ inch apart.
Combine oil, vinegar, garlic, salt, pepper, scallions. Parsley, Liquid aminos and rub your mushrooms. Seal tightly in either a gallon zip loc bag or in an aluminum covered tightly sealed baking dish. Let marinate for 1 hour.
Heat your oven grill and add a bit of oil to it. Carefully place your mushroom caps two at a time, grill on each side for 7 to 9 minutes each or until mushroom starts to cook down.
Serve with your Burger bun, lettuce, tomatoes, vegan mayonnaise etc. Enjoy!!