Preheat your grill to 275 degrees for two-zone cooking. That means that half of your grill has direct heat (charcoal, propane, etc) and the other half of the grill is heated only by the radiant heat from the other side (no direct heat).
In a small bowl, combine the mayonnaise and steak sauce for the burger sauce. Stir really well and then refrigerate until ready to use.
In a large bowl, combine the ground chuck and the small butter pieces. Don't over mix, just gently toss together to evenly distribute the butter. Form the meat into 8 oz patties that are just larger than the size of your buns. Season the patties on all sides with the Bent Burger seasoning.
Gently place the seasoned butter burger patties on the indirect side of the grill and close the lid. Cook for 4-5 minutes and then carefully flip the burger. Repeat until the burgers reach 145 degrees F internal temperature. As you get close to target temperature, it's a great time to place the buns on the direct heat and let them toast up for about 1-2 minutes.
Leave the lid of the grill open and transfer the patties to the direct heat of the grill. This part goes fast, so watch your internal meat temperature. Cook for 2-3 minutes, and flip once. Top with the cheddar cheese, cover the grill, and allow the patties to cook to 165 degrees F and the cheese to get all nice and melty.
Place the finished burgers on the toasted buns and top with all of your favorite burger toppings Don't forget the amazing burger sauce, it really adds so much!