01 -
Throw the chopped onions and ground beef into a big skillet set to medium-high. Sprinkle with beef bouillon powder, some salt, and a bit of pepper. Cook it until the beef turns brown. Add the garlic last, cooking for just about 30 seconds, then get rid of any extra grease.
02 -
Pour in the tomato sauce, brown sugar, ketchup, and mustard. Stir until everything's blended well and let it gently bubble on low to medium heat.
03 -
Spread a light mayo layer on one side of a bread slice. Place it mayo-side down in a skillet on medium heat. Stack a cheese piece, some of the beef mixture, another cheese piece, and a second bread slice (mayo-side faces up). Flip and cook until both sides are golden and crispy.
04 -
Serve nice and warm for an ultimate Sloppy Joe delight.