Preheat the oven to 350°F. Line a 12-cup muffin pan with cupcakes liners, and set aside.
In a small saucepan, melt the butter over medium heat and whisk often until it turns golden brown with a nutty aroma. Set aside to cool slightly.
1 cup unsalted butter
In a medium bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon, nutmeg, and ginger.
1 cup all-purpose flour, 1 teaspoon baking powder, ½ teaspoon baking soda, ½ teaspoon salt, 1½ teaspoons ground cinnamon, ½ teaspoon ground nutmeg, ½ teaspoon ground ginger
In a large mixing bowl, whisk together the browned butter, oil, eggs, brown sugar, vanilla, and sweet potato puree until smooth.
½ cup vegetable or canola oil, 2 large eggs, ¾ cup light brown sugar, packed, 1 teaspoon vanilla extract, 1 cup sweet potato puree
Gently fold the dry ingredients into the wet mixture until just combined. Do not overmix.
Divide the batter evenly among cupcake liners, filling each about ¾ full. Bake for 22–25 minutes, or until a toothpick inserted in the center comes out clean. Cool completely.
Once cooled, place a spoonful of marshmallow fluff on top of the each cupcake, then top mini marshmallows in a single layer so they stay in place.
Marshmallow Fluff, Mini marshmallows
Use a butane torch to gently toast the marshmallows until golden brown, mimicking a sweet potato casserole topping.
Serve and enjoy!