recipe for fresh tomatoes

Ingredients: 4-5 ripe tomatoes, sliced or chopped 1/2 red onion, thinly sliced 1/4 cup fresh basil leaves, torn or chopped 1/4 cup extra virgin olive oil 2 tablespoons balsamic vinegar Salt and pepper, to taste Optional: 1 clove garlic, minced Optional: 1/4 cup crumbled feta cheese or fresh mozzarella