Line a 4-inch wide lid with plastic wrap. Add a few spoonfuls of hamburger mixture to the lid and fold plastic wrap over the top to press and mold the burger patty. Unwrap from plastic wrap and place onto a plate or platter. Continue this process until you have created 8 patties, about 1/4 pound each, 1/3-1/2 inch thick, 4 inches across.

Cover and refrigerate for about 1 hour. (This will help the burgers keep their shape on the grill)

While burgers are resting, make the secret sauce: stir mayonnaise together with ketchup, pickles, pickle juice, ground pepper, and garlic powder. Place in refrigerator.

To grill, place each burger onto preheated grill. Cook 3 minutes on one side and then flip. Add cheddar cheese slices on each patty, cover and cook 1 minute. Turn grill off and then continue cooking another 3 minutes or until burgers register 160 degrees F.