01 -
Heat your oven to 400°F and get it ready.
02 -
Put the ground beef in a big pan over medium heat. Add a small dollop of butter or margarine, break the beef into small pieces, and cook it all the way through.
03 -
Once cooked, get rid of any grease left in the pan. Stir in the diced onions with the beef and keep cooking for a couple more minutes, giving it an occasional stir.
04 -
Take the pan off the heat. Toss in mayo, ketchup, mustard, onion powder, salt, pepper, and bacon. Stir it well so everything combines nicely.
05 -
Take 6 slices of bread, spread butter on one side, and slice each in half. Place them butter-side down in a greased 9 x 13 baking dish.
06 -
Spread half of your cheese mix evenly over the bread.
07 -
Scoop out the meaty mixture and evenly cover the cheese layer.
08 -
Sprinkle the remaining cheese across the meat layer.
09 -
Butter 6 more bread slices, cut them in half, and place them butter-side up on top of everything in the baking dish.
10 -
Pop the dish in the oven for about 20–24 minutes. You’ll know it’s done when the bread on top is golden and crisp.
11 -
After baking, let it rest on the counter for a bit before slicing and serving. Dig in and enjoy!