Alicia's Broiled Tomato Sandwich

I used sliced sourdough bread and four tomatoes (made a lot of tomatoes). I will probably start with two tomatoes next time and add more to the marinade if needed.
2 tablespoons olive oil
2 tablespoons balsamic vinegar
4 ripe tomatoes, sliced
3 tablespoons mayonnaise
1/2 teaspoon dried parsley
1/4 teaspoon dried oregano
1/4 teaspoon black pepper
3 tablespoons grated Parmesan cheese, divided
4 slices bread, lightly toasted

DIRECTIONS:
1. Preheat oven to broil.
2. In a shallow bowl, whisk together the olive oil and vinegar. Marinate the tomatoes in the mixture, stirring occasionally.
3. Meanwhile, in a small bowl, combine mayonnaise, parsley, oregano, black pepper and 4 teaspoons Parmesan cheese. Spread mixture on each slice of toasted bread. Place marinated tomatoes on 2 slices and sprinkle with remaining Parmesan cheese.
Place on a baking sheet and broil for 5 minutes, or until cheese turns golden brown. Serve immediately, open faced or closed.