Step 1: Cook the rotini pasta in a large pot of salted boiling water according to package directions, but aim for a slightly soft texture rather than firm al dente.
Step 2: Drain the pasta and immediately rinse under cold water until the noodles are completely cool to the touch.
Step 3: In a small bowl or jar, whisk together the olive oil, red wine vinegar, oregano, garlic powder, salt, and pepper to create the dressing.
Step 4: In a large mixing bowl, combine the cooled pasta, cherry tomatoes, cucumber, red onion, bell pepper, olives, and feta cheese.
Step 5: Pour the dressing over the salad and toss thoroughly to ensure every ingredient is coated; chill in the refrigerator for at least 30 minutes before serving.