- 1/4 cup soy sauce or liquid aminos
- 1/4 cup balsamic vinegar
- 2 tablespoons olive oil
- 3 garlic cloves, crushed
- 4 (4-inch) portabella mushroom caps
- Cooking spray
- 4 (2-ounce) sandwich buns
- 4 (1/4-inch-thick) slices tomato
- 4 curly leaf lettuce leaves
- Combine first 4 ingredients in a large zip-top plastic bag; add mushrooms to bag. Seal and marinate at room temperature for 2 hours, turning bag occasionally.
- Remove mushrooms from bag; discard marinade. Prepare grill to medium heat. Place mushrooms, gill sides down, on grill rack coated with cooking spray; grill 4 minutes on each side.
- Place buns, cut sides down, on grill rack coated with cooking spray; grill 30 seconds on each side or until toasted. Spread 2 tablespoons mayonnaise on top half of each bun. Place 1 mushroom on bottom half of each bun. Top each mushroom with 1 tomato slice and 1 lettuce leaf; cover with top halves of buns.
I tasted only a tiny corner of my vegetarian friend’s portabella burger as there were plenty of non-vegetarian bites at our Fourth of July cook out. I tasted enough to be able to rate the dish.
I soaked the cap for about four hours than what was specified in the directions and this is not something I would recommend. The mushroom absorbed a lot more liquid than I would have imagined. Later I attempted to squeeze some of the liquid out of the mushroom which only served to flatten cap.
Vegetarian? Try one of these vegetarian-friendly burgers: