Grilled Balsamic Marinated Portobello Mushroom Veggie Burgers Recipe :: The Meatwave

Ingredients

• 1/4 cup balsamic vinegar
• 1/4 cup olive oil
• 2 tablespoons juice from 1 lemon
• 1 tablespoon Dijon mustard
• 1 tablespoon freshly minced garlic
• 1 teaspoon finely minced thyme leaves
• 1 teaspoon Kosher salt
• 4 portobello mushrooms, stems removed and scrubbed clean
• 4 hamburger buns
• 4 pieces of green or red leaf lettuce, washed and dried
• 1 roma tomato, sliced
• 1 red onion, thinly sliced