In a large bowl mix together Hamburger, Worcestershire, Garlic, Onion, Pepper, Burger Seasoning & Cajun. (Those are the seasonings I normally use on burgers, but I want you to use what your family likes.) Set aside.
Preheat oven to 375.
Prep your cookie sheet by lining it with aluminum foil (shiny side up, it makes clean up easier and the shiny helps to bake more evenly). Set a cooling rack on top of the foil (if it has legs, collapse the legs. You want the burgers slightly elevated so they cook consistently, but you don't want them raised very much or you'll have a lot of grease splatter and potentially smoke to contend with. Spray generously with non-stick spray.
Form 6 patties from your burger and space evenly on rack on cookie sheet.
Bake 25-35 minutes until they reach the doneness level you want. (Granddaughter of a butcher here - there are some things that you just don't do and pink burgers is one of them! You might like the pink though. Do what works for you.)
Remove from oven, top with Cheese Slices, place back in oven, turn off. It only takes about 2 minutes for the ooey-gooeyness to happen.