1Flatten the ground beef into rectangular patties on parchment paper.
2Flatten the ground beef into rectangular patties on parchment paper.
3Flatten the ground beef into rectangular patties on parchment paper.
4Season the beef patties generously.
5Season the beef patties generously.
6Season the beef patties generously.
7Dice the bacon into small pieces.
8Dice the bacon into small pieces.
9Dice the bacon into small pieces.
10Turn on the griddle to medium heat.
11Turn on the griddle to medium heat.
12Turn on the griddle to medium heat.
13Cook the diced bacon on the griddle until crispy, then remove and set aside.
14Cook the diced bacon on the griddle until crispy, then remove and set aside.
15Cook the diced bacon on the griddle until crispy, then remove and set aside.
16In a bowl, combine mayonnaise, balsamic vinegar, honey, ketchup, yellow mustard, red pepper flakes, and the cooked bacon pieces.
17In a bowl, combine mayonnaise, balsamic vinegar, honey, ketchup, yellow mustard, red pepper flakes, and the cooked bacon pieces.
18In a bowl, combine mayonnaise, balsamic vinegar, honey, ketchup, yellow mustard, red pepper flakes, and the cooked bacon pieces.
19Mix well until all ingredients are thoroughly combined to create the baconnaise sauce.
20Mix well until all ingredients are thoroughly combined to create the baconnaise sauce.
21Mix well until all ingredients are thoroughly combined to create the baconnaise sauce.
22Slice the onions thinly using a mandoline slicer.
23Slice the onions thinly using a mandoline slicer.
24Slice the onions thinly using a mandoline slicer.
25Place the sliced onions on the griddle and season with salt.
26Place the sliced onions on the griddle and season with salt.
27Place the sliced onions on the griddle and season with salt.
28Cook the onions until caramelized and tender, then add a splash of balsamic vinegar and mix.
29Cook the onions until caramelized and tender, then add a splash of balsamic vinegar and mix.
30Cook the onions until caramelized and tender, then add a splash of balsamic vinegar and mix.
31Butter slices of sourdough bread and toast them on the griddle until golden brown and crispy on both sides.
32Butter slices of sourdough bread and toast them on the griddle until golden brown and crispy on both sides.
33Butter slices of sourdough bread and toast them on the griddle until golden brown and crispy on both sides.
34Cook the seasoned beef patties on the griddle until browned and cooked through, adding bacon bits and American cheese slices on top as they cook to melt the cheese.
35Cook the seasoned beef patties on the griddle until browned and cooked through, adding bacon bits and American cheese slices on top as they cook to melt the cheese.
36Cook the seasoned beef patties on the griddle until browned and cooked through, adding bacon bits and American cheese slices on top as they cook to melt the cheese.
37Spread a generous layer of baconnaise sauce on one slice of toasted sourdough bread.
38Spread a generous layer of baconnaise sauce on one slice of toasted sourdough bread.
39Spread a generous layer of baconnaise sauce on one slice of toasted sourdough bread.
40Place a cooked patty with melted cheese and bacon on top of the sauce.
41Place a cooked patty with melted cheese and bacon on top of the sauce.
42Place a cooked patty with melted cheese and bacon on top of the sauce.
43Add a generous amount of caramelized onions on top of the patty.
44Add a generous amount of caramelized onions on top of the patty.
45Add a generous amount of caramelized onions on top of the patty.
46Top with another slice of toasted sourdough bread.
47Top with another slice of toasted sourdough bread.
48Top with another slice of toasted sourdough bread.
49Gently press the sandwich to combine the layers.
50Gently press the sandwich to combine the layers.
51Gently press the sandwich to combine the layers.