Wash and dry the cherry tomatoes. Cut each one in half crosswise and set aside. If needed, trim a thin sliver from the flat cut side so the tomato sits level.
Use a toothpick to dab small dots of mayonnaise across the rounded surface of each tomato half, spacing them out to resemble toadstool spots.
While the mayonnaise is still tacky, press one white sesame seed onto each dot. Set decorated tomato caps aside on a plate.
Skewer one mozzarella ball onto a toothpick, pushing it most of the way through and leaving a small tip of the toothpick exposed at the top.
Place the mozzarella ball onto a fresh basil leaf on your serving tray or board.
Gently press a decorated tomato half onto the exposed toothpick tip so it sits like a cap on top of the mozzarella ball.
Repeat with remaining ingredients. Arrange finished toadstools on a wooden board or platter lined with extra basil leaves or fresh greens.
Refrigerate until ready to serve. Best enjoyed within a few hours of assembly.
