Macaroni Salad With Ham with tenders

8 ounces elbow macaroni , cooked until firm-tender 3/4 cup mayonnaise (not salad dressing) 1/4 cup plain yogurt 2 tablespoons cider vinegar 1 tablespoon Dijon[...]

12 ounces Spam (my husband is a vegetarian so I use morningstar veggie hot dogs or Loma Linda lunch meat) 1 1/2 cups ham , can be used instead 1 (20 ounce)[...]

3 quarts boiling water 1 tablespoon salt 8 ounces elbow macaroni 10 ounces frozen peas, cooked, drained 1 cup diagonally sliced celery 1 cup snipped scallion[...]