1. Spread about 1 1/2 teaspoons mayonnaise on one side of each toasted white bread slice.
2. Arrange the turkey breast on one slice of toast.
3. Tear or fold one iceberg lettuce leaf to fit on the sliced turkey.
4. Stack on another slice of toast with the mayo side facing up.
5. Break 2 or 3 slices of cooked bacon to fit on top of the second slice of toast.
6. Tear or fold the second lettuce leaf to fit on top of bacon.
7. Arrange the two tomato slices to fit on the lettuce.
8. Top off the sandwich with the last piece of toast turned with the mayo-coated side facing down.
9. Pierce the sandwich with four toothpicks between the corners, so that when the sandwich is sliced twice from corner to corner with a serrated knife, the toothpicks wind up in the center of each of the four slices.