Combine olive oil and herbs in a small bowl and let sit for at least 30 minutes to allow the herbs to soften. Drain mozzarella balls, then toss them in the olive oil mixture. Slice tomatoes in half.

To assemble, place one half of a tomato on a skewer, followed by a mozzarella ball, followed by another half of tomato. Arrange skewers on a tray, and drizzle with balsamic vinegar.