01 -
In a large skillet over medium-high heat, cook the diced onions and ground beef seasoned with beef bouillon powder, salt, and pepper until the beef is no longer pink. Add minced garlic and sauté for 30 seconds. Drain excess grease.
02 -
Stir in tomato sauce, ketchup, mustard, and brown sugar. Mix well and bring to a gentle simmer over low-medium heat.
03 -
Spread mayonnaise on one side of each bread slice. Place mayo-side down in a skillet over medium heat. Layer with cheese, a scoop of sloppy joe mixture, and another cheese slice. Top with another slice of bread, mayo-side up.
04 -
Grill sandwiches until golden brown on both sides. Serve hot.