Preheat oven to 325°. Place bread slices on ungreased baking sheets; brush with 1/4 cup oil. Bake until golden brown, 10-12 minutes., In a small bowl, whisk together vinegar and remaining oil. Stir in tomatoes, onion, cilantro, salt and pepper., To serve, spoon scant 1 tablespoon tomato mixture onto each slice of bread. Top with cheese.