Combine Ground Beef, Worcestershire Sauce, Garlic Salt, And Pepper In A Large Bowl; Mix Well. Form 8, Thin Patties From The Beef. Each Patty Should Be Slightly Larger Than A Slice Of Cheese. Cut Each Slice Of American Cheese Into 4 Equal Pieces; Stack The Pieces. Sandwich One Stack Of Cheese Between 2 Ground Beef Patties. Tightly Pinch Edges Together Tightly Seal The Cheese Within The Meat. Repeat With The Remaining Cheese And Patties. Preheat A Cast-Iron Or Other Heavy Bottomed Skillet Over Medium Heat. Cook Burgers Until Well Browned, About 4 Minutes. It Is Common For Burgers To Puff Up Due To Steam From The Melting Cheese. Turn Burgers And Prick The Top Of Each To Allow Steam To Escape; Cook Until Browned On The Outside And No Longer Pink On The Inside; About 4 Minutes. Serve On Hamburger Buns.