To assemble stacks, place a layer of eggplants on the sheet. Cover each eggplant slice with a slice of tomato (even cut some tomato pieces in half to ensure that as much of the eggplant is covered as possible), and follow with some grated cheese.
Drizzle each stack with your diluted vegan mayonnaise sauce, and sprinkle salt and pepper and your herbs. Cover the sheet with tinfoil (At this point, this can be assembled ahead of time and left to rest in the fridge for up to a day).
Turn off oven and let tray eggplant stacks rest in it, undisturbed, for another 5 mins. Serve immediately (though stacks are fine if refrigerated and reheated later, they must be bubbling hot when consumed).