Oil the grill grates then preheat grill to medium-high.
Cut a large zucchini into thick slices about 3/4 inch thick.
Grill the zucchini slices 7 minutes total, or until there are some grill marks on the bottom side and it’s starting to be tender.
If the zucchini has a side that’s slightly larger, grill that first so it will be the top
If desired, you can heat the sauce while the zucchini grills.
Remove zucchini from the grill, putting them grilled-side up on a cutting board you can use to take them to the kitchen
Add 1 tablespoon sauce to each zucchini slices.
Then top with one tablespoon Mozzarella cheese cheese
Put 4 slices pepperoni over the cheese
Put a tiny bit more cheese over the pepperoni.
Put loaded zucchini slices back on the grill and cook 7 minutes on the second side with the grill lid closed.
Remove zucchini pizzas from grill and serve hot.