Preheat the Blackstone Grill over medium high heat (approximately 400 degrees F).

Mix the ground beef, salt, pepper, Worcestershire sauce and garlic powder together in a bowl.

Divide the ground beef into 6 even balls (approximately ⅓ lb each).

Divide each ball in half and form into two thin patties.  Place approximately 2-3 tablespoons of the shredded cheese in the center of one patty and then top with the other patty.  Seal the edges by pinching them together.

Melt the butter onto the Blackstone Grill and spread it around.

Place the ground beef patties on the Blackstone grill on the butter.

Gently press flat onto the Blackstone Grill making sure that you do not expose the cheese.  Do not smash it all the way down but just press slightly to form a burger patty.

Cook the patties for 3-5 minutes.

Flip the burgers and cook until burgers are cooked through (3-4 more minutes).

Remove the patties from the grill.

Place the buns on the grill, cut side down for approximately 1 minute until browned.  Remove the buns from the grill.

Add a lettuce leaf and onions to the bottom bun of each bun.

Add beef to each of the hamburger buns on top of the lettuce.

Then top each patty with the tomatoes and condiments of your choice.  Serve warm and enjoy!