Preheat the oven to 365 degrees F.
Scrub the potatoes clean then cut parallel lines into the potatoes lengthwise, but do not cut through. Lie wooden spoons or chop sticks next to the potatoes to keep you from cutting all the way through, if needed.
Line a baking sheet with parchment paper and spray with non stick cooking spray.
Place the potatoes onto the baking sheet and drizzle with olive oil.
Sprinkle each potato with salt, pepper and Italian seasoning.
Bake in a preheated oven for 50-60 minutes or until fork tender.
Remove from the oven and stuff the potatoes with pepperoni slices.
Pour the tomato sauce over the baked potatoes and top with mozzarella cheese.
Bake in a preheated oven again for 10 more minutes at 365 degrees F.
Broil for 2 minutes if desired but keep an eye on the potatoes so they don’t burn.
Top with grated parmesan cheese and fresh parsley if desired before serving.