Dice the onion and tomatoes.
Mince the garlic and coarsely chop the fresh basil.
Combine the tomatoes, onion, garlic, and basil in a medium mixing bowl.
Add 2 Tbsp. of balsamic vinegar.
Toss in a pinch of salt and pepper and the grated Parmesan cheese.
Stir together.
Serve as a dip or on grilled bread, a crostini, or a baguette. You can also use this bruschetta to top a chicken or fish dish.