Cool Crunchy Pasta Salad

1 C nonfat yogurt
3 Tbsp white wine vinegar or cider vinegar
3 Tbsp chopped black olives
1 Tbsp chopped fresh or 1 tsp dried thyme
1 clove garlic, minced
salt and pepper to taste
12oz fusili (corkscrew), penne or other large pasta shape
1 (6 1/8oz) can water-packed tuna, drained
1/2 C chopped walnuts
1/4 C thinly sliced roasted, peeled red peppers (packed in jars)
2 Tbsp chopped parsley

To make dressing, in small bowl place the yogurt, vinegar, olives, thyme and garlic. Stir to combine, then season with salt and pepper to taste. Set aside. Cook the pasta in boiling salted water until done. Drain in a colander, then rinse well and drain again. Place in a large bowl with the tuna, walnuts and peppers and toss to combine. Before serving, add the dressing and stir to coat the ingredients evenly. Sprinkle with parsley.