Make dressing: In a small bowl, whisk together garlic, oregano, mustard, vinegar, salt, pepper and olive oil until well combined.
Make salad: Bring a large pot of salted water to a boil. Add pasta and cook until al dente, about 8 minutes, or as label directs. Drain, rinse under cold water and transfer to a bowl. Add remaining ingredients, toss with dressing and serve.