Brown Butter Sweet Potato Cupcakes with Homemade Bourbon Marshmallows
Heather Baird
These sweet potato cupcakes were inspired by my mom’s Thanksgiving side dish of sweet potatoes topped with marshmallows. There are several steps to this recipe, but I think they are well worth the effort. And especially for the upcoming holidays! You can buy unsweet sweet potato puree canned at most grocery stores, and that’s what I used in this recipe. However, you can also make your own by peeling sweet potatoes, cutting them into 1/2 inch chunks, and boiling them until tender (about 15 minutes). Then mash them until fine, or stick them in a blender to puree.
Preheat oven to 350 degrees. Line cupcake tins with papers.
Melt the butter in a saucepan over medium heat. Use a light-colored metal saucepan so you can easily see the color of the butter change. It’s much harder to judge the doneness in a dark nonstick pan. Cook until the butter foams and steams. Swirl the pan occasionally as the foam subsides and watch closely as the butter turns golden brown and the milk solids drop to the bottom of the pan. Pour the browned butter and butter solids into a small bowl and let stand until cool but not solidified.
In a medium bowl, whisk the flour, baking soda, cinnamon, ginger, allspice, and salt. Set aside.
In a large bowl, whisk the sweet potato puree with the granulated sugar, brown sugar, eggs and sour cream until well combined. Stir in the flour mixture and combine until only a few streaks of flour remain. Whisk in the browned butter until well combined.
Divide the batter between the cupcake liners using a trigger ice cream scoop. If you don’t have a scoop, fill them about approximately 2/3 full. Bake cupcakes for 20-25 minutes or until they spring back when pressed in the middle. Remove them to a wire rack to cool completely.
Bourbon marshmallows
Lightly spray an 8-by-8-inch baking pan with cooking spray and wipe away any excess with a paper towel.
Let the gelatin dissolve in bourbon 5 minutes, or until well bloomed and thickened.
In a medium saucepan with a candy thermometer clipped to the side, stir together the sugar, 1/4 cup corn syrup, 1/4 cup water and salt and place over high heat. Boil, stirring occasionally, until the temperature reaches 240°F. Meanwhile, pour the remaining 1/4 cup corn syrup into the bowl of an electric mixer fitted with the whisk attachment.
Microwave the gelatin on high until it is completely melted, about 10-20 seconds. Pour it into the corn syrup. Set the mixer to low, and keep the mixer running while you check the sugar syrup.
Once the syrup reaches 240°F, remove it from the heat. Keeping the mixer on low, slowly pour the syrup into the gelatin mixture in a steady stream, aiming for the space between the beater and the bowl. Increase the speed to medium and beat for 5 minutes. Raise the speed to medium-high and beat for 5 more minutes. Beat on the highest setting for 1 to 2 minutes more and beat in the 2 tablespoons bourbon; the finished marshmallow will be opaque white, fluffy, and roughly tripled in volume.
Pour the marshmallow into the prepared pan. Use an offset spatula to smooth the top. Combine cornstarch and confectioners’ sugar in a medium bowl to make the coating. Sift coating evenly and generously over the top. Let the marshmallow set for at least 2 hours. When the marshmallow has set, use a knife to loosen the marshmallow from the edges of the pan. Invert the marshmallow slab onto a coating-dusted work surface and dust it with more coating. Cut into 25 large squares and dip the sticky edges of the marshmallows in more coating, patting off the excess. Let stand, uncovered, at room temperature while you prepare the buttercream.
Cinnamon buttercream
Combine the butter and confectioners in the bowl of an electric mixer. Beat on high speed until well combined, about 4 minutes. Add in the cinnamon. Add milk or cream 1 tablespoon at a time with the mixer running until the frosting comes to piping consistency. Transfer the frosting to a large piping bag fitted with a large sultan decorator piping tip (see blog post for link). Alternatively, you can use any large fluted piping tip.
Assembly
Pipe a small ring of buttercream on a cupcake and immediately top with a marshmallow. Repeat the process of piping and topping until all of the cupcakes are topped. Use a chef’s torch to lightly toast the marshmallows. Homemade marshmallows are extremely meltable, so use a light touch. Garnish each cupcake with a drizzle of caramel and a sprinkle of chopped pecans.
Store the cupcakes airtight for up to 2 days at room temperature.
Notes
If you don't have a chef's torch, place the marshmallows on a baking sheet and broil them for 2 minutes in the oven. As I stated before, homemade marshmallows are very meltable. When lightly toasted remove them from the oven and place them in the refrigerator to firm. When firm enough to move, transfer them with a spatula to the frosted cupcakes.To shortcut this recipe, you could use ready-made jumbo marshmallows instead of making the homemade bourbon marshmallows.