Preheat oven to 350°. Place bottoms of rolls, cut side up, in a 9-inch square cast-iron skillet. Sprinkle with 1 cup cheese.
In a large cast-iron skillet, heat oil over medium-high. Add beef, onion, and steak seasoning; cook, stirring occasionally, until beef is browned and crumbly and onion is tender, about 8 minutes. Stir in 1½ teaspoons Worcestershire sauce and tomato paste; cook for 1 minute. Stir in green onion. Spoon beef mixture in an even layer on rolls; top with bacon, remaining 1 cup cheese, and rolls, cut side down.
In a small bowl, whisk together melted bacon drippings, brown sugar, mustard, and remaining 2 teaspoons Worcestershire until smooth. Brush onto rolls; sprinkle with sesame seeds.
Bake until golden brown and heated through about 20 minutes. Serve immediately.
Recipe by Southern Cast Iron at https://southerncastiron.com/bacon-cheeseburger-pull-apart-sliders/