Tuna Souvlaki Pasta Salad

½ red onion, cut into bite-size pieces

4 cups ice water, or as needed

1 (8 ounce) package tri-color rotini pasta

1 (5 ounce) can light tuna in water, drained and flaked

2 stalks celery, cut into bite-size pieces

½ cup roasted red peppers, drained and chopped

¼ cup smoked sun-dried tomatoes

¼ cup crumbled feta cheese

1 sprig parsley, stemmed and leaves minced

4 leaves fresh basil, rolled and very thinly sliced

2 teaspoons capers

1 cup Greek vinaigrette salad dressing

Soak red onion in a bowl of ice water in refrigerator to remove strong taste, at least 30 minutes. Drain and rinse.

Bring a large pot of lightly salted water to a boil; cook the rotini at a boil until tender yet firm to the bite, about 8 minutes; drain and rinse under cold water.

Mix onion, pasta, tuna, celery, roasted red peppers, sun-dried tomatoes, feta cheese, parsley, basil, capers, and Greek dressing together in a large bowl. Allow to marinate in refrigerator, 4 hours to overnight.