1. Place chicken breasts smooth-side down on a cutting board. Pull or cut tenders from breast halves and save for another use.
2. Place a sheet of parchment or waxed paper over chicken pieces and pound lightly to an even thickness.
3. Bring 8 cups water, bay leaves and peppercorns to barely a simmer over medium heat in a large saute pan. Add chicken and cook for 10 to 12 minutes, keeping temperature moderate so only a few bubbles appear around chicken. Remove chicken when instant-read thermometer inserted in breasts registers 160 degrees . Refrigerate until cold.
4. Cut chicken into 3/4-inch cubes, stir together with mayonnaise, salt and pepper, and then with one of the flavor combinations below.