Portobello Mushroom Sandwich

Ingredients (18)

• 4 portobello mushrooms, stems removed
• 2 Tablespoons olive oil
• 1/4 cup balsamic vinegar
• 3 cloves garlic, minced
• 1 Tablespoon lemon juice
• 1 Tablespoon soy sauce
• 3/4 teaspoon Kosher salt
• 1/2 teaspoon ground black pepper
• 1/2 cup mayonnaise
• 1/4 cup roughly chopped chives
• 1 teaspoon dijon mustard
• 1 clove garlic
• Squeeze of lemon
• Salt, to taste
• 4 slices Swiss cheese
• 4 brioche buns
• 1 cup mixed greens and/or sprouts
• 6 ounces of jarred roasted red bell peppers, sliced