Fill a large pot with salted water and bring it to a rolling boil. Add pasta and cook until al dente, about 8-10 minutes. Drain and let cool.

In a mixing bowl, combine halved tomatoes, minced garlic, chopped shallot, and bocconcini. Drizzle with olive oil and vinegar, add basil, salt, and pepper. Toss and marinate for 10 minutes.

For optional breadcrumbs, preheat oven to 375°F (190°C). Toast sourdough until golden, about 10 minutes, then process into crumbs.

In a skillet, heat olive oil and add breadcrumbs. Sauté until crispy, about 5 minutes.

Fold cooked pasta into the salad mixture. If using, mix in breadcrumbs. Toss well to combine.

Let salad sit for at least 15 minutes before serving. Can be served cold or at room temperature.