Cut a 3-inch wide pocket in each steak, being careful not to cut through back or sides of steak. Fill pocket of each steak with 2 tablespoons of the blue cheese. Press steak lightly to seal closed.
Brush steaks with butter. Sprinkle with Seasoning.
Grill steaks over medium-high heat 6 to 8 minutes per side or until desired doneness. Sprinkle steaks with additional blue cheese, if desired.