01 - Toast all 6 slices of sandwich bread until golden brown and lightly crisp.
02 - Spread mayonnaise evenly over one side of each toasted bread slice.
03 - Place 2 slices of toast mayo-side up on a flat work surface. Layer each with half of the turkey or chicken breast, 1 slice of ham if using, 2 strips of bacon, sliced tomato, and a leaf of lettuce. Season with salt and pepper.
04 - Top each stack with a second toasted bread slice, mayo-side up. Repeat the layering with the remaining turkey or chicken, ham, bacon, tomato, and lettuce. Season again with salt and pepper.
05 - Place the third toasted bread slice on top of each sandwich, mayo-side down, to complete the triple-decker assembly.
06 - Insert 2 toothpicks into each sandwich to hold the layers together. Using a sharp knife, cut each sandwich diagonally into quarters to create classic wedge-shaped servings.
07 - Serve immediately while the bread is still warm, accompanied by potato chips or a side salad if desired.