Step 1

Cook the shells according to package instructions, being sure not to over cook. Drain and rinse with cold water.

Step 2

In a small bowl, whisk together the mayonnaise, yogurt, lemon juice, dill, salt and pepper.

Step 3

Add the noodles, tuna, peas, celery, and onion to a large bowl. Pour dressing over it, and toss to combine.