01 - Toast all 6 slices of sandwich bread until golden brown on both sides.
02 - Spread mayonnaise evenly over one side of each toasted bread slice.
03 - Place 2 slices of toast mayo-side up on a clean work surface. Layer each with half of the turkey or chicken, 1 slice of ham if using, 2 strips of bacon, sliced tomato, and a lettuce leaf. Season lightly with salt and pepper.
04 - Top each assembled layer with a second toasted bread slice, mayo-side facing up.
05 - Repeat the layering on each sandwich with the remaining turkey or chicken, ham, bacon, tomato slices, and lettuce. Season again with salt and pepper.
06 - Place the third toasted bread slice on top of each sandwich, mayo-side facing down to complete the triple-decker stack.
07 - Insert 2 toothpicks into each sandwich to hold the layers together. Using a sharp knife, cut each sandwich diagonally into 4 triangular wedges.
08 - Arrange the wedges on plates and serve immediately with chips or a side salad if desired.