For the Sauce
In a small bowl, whisk together the mayonnaise, bbq, ketchup, and mustard.
Stir in the relish, Worcestershire, and seasonings.
Set aside until you're ready to assemble.
Prepare the tomatoes and lettuce, set aside.
Heat the grill to high heat.
Brush the grates with a little oil.
Separate the meat into four patties and press out flat, making an indentation right in the center to promote even cooking and less shrinking.
Sprinkle with salt and pepper and place a dollop of butter on top.
Place each patty on the grill and turn to medium high.
Cook on one side for about 2-3 minutes, if the burger is ready to be flipped it will release from the grates, if not allow it to cook a moment more.
Flip and season the other side, adding your cheese, shutting the lid and cooking for an additional 2-3 minutes.
Meanwhile, brush a little butter on the inside and outside of the buns.
Place bottom down on the grill and toast only until grill marks appear.
Remove from grill, slather each bun with sauce, lettuce, tomato, and finally the patty, the center should be slightly pink when done.
Top with the other half of the bun and enjoy!