If you’re using a torch (the preferred method), make sure the area you’re working in is clear of any plastic, paper, or other flammable items and that the surface you’re working on is fireproof (steel, marble, etc.). Slide a baking sheet under the pie to protect your countertops. Light the torch and lightly toast the surface of the pie, going as toasty as you prefer. When the pie is perfectly brûléed, turn off the torch and let the pie cool for 10 minutes.
If you’re torchless, you can toast the marshmallow fluff topping under the broiler, but keep a close eye on the pie and bear in mind that this technique requires patience, watchfulness, and speed. You’ll need to preheat your broiler, slide the pie on a baking sheet, and use foil or a pie shield to cover the crust edges. Broil the pie about 3 inches from the heat source, rotating it to ensure even toasting, until the topping is the desired shade of toasted goodness. It burns very easily with this method, so watch closely! It’s best to keep the oven door cracked open so you can keep a watchful eye on the pie, rotating it as needed, the entire time. Remove the pie from the oven and let it cool for at least 10 minutes.