What a great appetizer, and sooo easy to make! Farm fresh, in-season tomatoes work best, but any good greenhouse tomato would work well also. I have given quantities as it depends on how many you want to make.
2 large tomatoes
extra virgin olive oil
dab of really good balsamic vinegar
Slice tomatoes almost all the way but not quite. Slice mozzarella in thin slices. Place a basil leaf on top of a mozzarella slice and place in the slice of the tomato.
Drizzle with olive oil and a little balsamic.