Preheat the oven or grill to 400°F. (If cooking over an open flame without a thermometer, be aware that time may vary slightly.)
Place the potatoes and tomatoes on top of a large square of aluminum foil. Drizzle with the olive oil and season with the Italian seasoning, crushed red chili flakes, salt, and pepper.
Wrap the foil around the food by creating an envelope style fold over the top and rolling the edges up. This will make it easier to check the potatoes for doneness. It also makes for easy serving.
Place the foil pouch into the oven or over the campfire on a grate. Allow it to cook, rotating the foil package around the heat from time to time to prevent scorching, for about 25 minutes or until the potatoes are tender.
To finish the dish, top the potatoes and tomatoes with the shredded mozzarella cheese and place back in the oven or on the fire for just a few more minutes to allow the cheese to melt. Add the pepperoni on top and sprinkle with basil before enjoying.