This miniaturized version of a traditional Caprese salad is easily made ahead and spooned in to leak-proof canning jars for an easily transported picnic-friendly side.
Put oil into a medium bowl; season with salt and pepper. Add bocconcini, tomatoes, and basil; toss gently. Divide among 6 jars or serving dishes. If not serving within 3 hours, refrigerate until ready to use, up to 8 hours.