In a large skillet over medium heat, add the thinly sliced onions and cook for 2-3 minutes until softened and fragrant.

Next, add the ground beef to the skillet with the onions. Cook, breaking up the meat with a wooden spoon, until browned and crumbled.

Drain any excess grease, leaving about 1/2 tablespoon.

Stir in the Worcestershire sauce, black pepper, onion powder, and cayenne (if using). Cook for another 1-2 minutes to let the flavors mingle together.

Next, reduce heat to low and add the cubed Velveeta cheese, stirring until completely melted and coating the beef mixture evenly.

Spoon the cheesy meat mixture onto the bottom half of each roll. Top with a pickle slice (if using) and place the top half of the roll on top.

Serve warm and enjoy!