American Macaroni Salad Recipe

Ingredients

• 2 cups dry pasta shell macaroni
• 1/3 cup celery
• 1/4 cup red onion, soaked in cold water for 5 minutes, drained
• 1 tablespoon fresh flat-leaf parsley
• 1/2 cup diced tomato (optional)
• 1/2 cup prepared mayonnaise
• 3/4 teaspoon dry mustard
• 1 1/2 teaspoons sugar
• 1 1/2 tablespoons cider vinegar
• 3 tablespoons sour cream
• 1/2 teaspoon kosher salt, plus more to taste
• fresh ground black pepper