01 -
Heat a sauté pan over medium heat. Add ground beef, season with salt and pepper, and cook, breaking apart with a spatula, until well browned, about 5 minutes. Remove beef from pan and set aside. Drain excess grease from the pan if needed.
02 -
Add butter to the same pan. Once melted, add diced onion and bell pepper. Sauté until vegetables are golden and onions are translucent, about 4–5 minutes.
03 -
Lower the heat to low. Return ground beef to the pan. Add garlic powder (or minced garlic), Worcestershire sauce, and beef broth, scraping any browned bits from the bottom. Stir and cook for about 1 minute.
04 -
Add cornstarch and stir thoroughly until completely dissolved, about 1 minute, to thicken the mixture. If the beef appears dry, add 15–30 millilitres water.
05 -
Remove from heat. Arrange cheese slices evenly over the beef mixture and cover the pan. Let sit for 1–2 minutes, until cheese is melted.
06 -
Evenly spoon the hot beef and vegetable mixture onto sandwich rolls. Serve immediately while warm.