Toast the white bread until golden brown. Use a round cookie cutter to cut 4 circles out of the center of the toast.
Use the same cookie cutter to cut a circle out of the ham slices. The stack of ham slices should be roughly the same height as a piece of toast. Place the ham circle in the hole in one piece of toast and place a toast circle in the hole in the stack of ham.
Repeat the process with the salami.
Fry the ground beef patty, cut out a circle, and put a toast circle into the hole in the patty.
Cut out a circle out of the camembert cheese wheel with the cookie cutter and place the cheese circle in the hole in a piece of toast.
Repeat step #3 with the cheddar cheese slices.
Repeat the process with the Swiss cheese.
Assemble your breakfast sandwich tower in the following order: toast with ham, tomato slice, mayonnaise, ground beef patty with toast, avocado slices, ketchup, cheddar cheese with toast, tomato slice, mayonnaise, toast with salami, avocado slices, ketchup, ham with toast, tomato slice, mayonnaise, toast with camembert, avocado slices, ketchup, Swiss cheese with toast, bacon slices.
Crack the egg into a pan, fry it, and place the last slice of toast on top so that the hole and the egg yolk line up. Put this slice on top of the sandwich tower and fix everything in place with long wooden skewers. Transfer the tower to a sheet pan and cook in a preheated oven set to 325°F for 12 minutes.