Cook pasta in salted boiling water until al dente according to package directions (about 8-10 minutes). Drain and rinse under cold water to stop cooking.
While pasta cooks, make the dressing: In a small bowl or jar, whisk together olive oil, red wine vinegar, Dijon mustard, minced garlic, oregano, salt, and pepper.
In a large bowl, combine cooled pasta, quartered pepperoni, mozzarella pearls, halved cherry tomatoes, diced bell peppers, sliced olives, red onion, and fresh basil.
Pour the dressing over the salad and toss gently until everything is evenly coated.
Cover and refrigerate for at least 30 minutes to allow flavors to meld. Toss again before serving.