01 - Lay out the bread slices on a clean cutting board or flat surface.
02 - Spread mayonnaise evenly on one side of each bread slice using a butter knife or spreader.
03 - Arrange the thinly sliced tomatoes on two of the bread slices, slightly overlapping each piece for even coverage.
04 - Sprinkle the tomato layers evenly with kosher salt and freshly ground black pepper to taste.
05 - Tuck fresh basil leaves over the seasoned tomatoes if using, for added brightness and herbaceous flavor.
06 - Place the remaining bread slices on top, mayonnaise side facing down, and gently press each sandwich together.
07 - Cut each sandwich in half diagonally or straight down the middle, then serve immediately for optimal texture and freshness.