Begin by boiling a large pot of salted water. Add 16 ounces of rotini pasta and cook according to package instructions until al dente, usually about 8-10 minutes. Drain and cool.

While the pasta cools, wash and dice your cucumber, carrot, sweet onion, and bell pepper into bite-sized pieces. Pit and slice the Kalamata olives. Combine the vegetables in a large mixing bowl.

In a mason jar, mix 1 cup of plain unsweetened Greek yogurt, 2 tablespoons of red wine vinegar, the juice of one lemon, and a minced garlic clove. Add onion powder, dried oregano, and fresh dill. Shake until well blended.

Add the cooled rotini to the bowl of mixed vegetables, pour the tzatziki dressing over the top, and gently toss until well-coated.

Cover the bowl and refrigerate the salad for at least one hour before serving. Toss again before serving.