Cook bacon in a skillet over medium heat until crispy, about 6-8 minutes. Transfer to paper towels to drain excess grease.
Butter all three bread slices on one side. Toast in the same skillet, buttered side down, until golden brown, about 2-3 minutes per side.
Spread mayonnaise on one side of the first toasted slice. Layer with lettuce and tomato slices, then season tomatoes with salt and pepper.
Place the second bread slice on top, mayo side down. Spread mayonnaise on the top side of this middle slice.
Layer the turkey and crispy bacon on top of the middle slice.
Crown with the third bread slice, mayo side down.
Secure the sandwich with 4 sandwich picks, one in each quarter.
Using a sharp knife, cut diagonally into quarters, cutting through the picks.