Preheat oven to 400°
Cut the stemmed top off the tomato.
Cut a very small piece off the bottom of the tomato so that tomato will sit upright in the dish.
Add the tomatoes to a glass baking dish.
In a bowl, add the mayo, cheese and breadcrumbs until well blended.
Generously top each tomato with the mayo mixture.
Bake the tomatoes in the oven for 10 minutes, until the crust is golden.