01 -
Start by preheating your broiler. This will be used at the end to melt the cheese on top of your sloppy joes.
02 -
In a small bowl, whisk together the cornstarch and beef broth until well combined. Set this mixture aside - it'll be used later to thicken the sauce.
03 -
Heat olive oil in a large nonstick skillet over medium-high heat. Add the diced onion, green bell pepper, and chopped mushrooms. Sauté for about 3 minutes until the vegetables begin to soften and become tender.
04 -
Add the ground beef to the skillet with the vegetables. Continue cooking while breaking up the meat with a wooden spoon or spatula. Brown for about 3 minutes, then drain off any excess fat from the pan.
05 -
Stir in the ketchup, Worcestershire sauce, taco seasoning, salt, and black pepper. Mix well to combine all the flavors with the meat and vegetables.
06 -
Give the cornstarch and broth mixture a quick stir again (as it may have settled), then pour it into the skillet. Allow everything to simmer for about 3 minutes, stirring occasionally, until the mixture thickens slightly.
07 -
Scoop the meat mixture onto the hamburger buns, then top each with about 1/4 cup of shredded cheese. Place the open-faced sandwiches under the broiler until the cheese melts - this happens quickly, so keep a close eye on them to prevent burning! Alternatively, you can simply stir the cheese directly into the meat mixture until melted.