Sweet potatoes flavor and color a batch of light-as-air, bite-sized pastries—and are then filled with an irresistible brown sugar marshmallow cream that’s toasted with a torch. Dessert, anyone?
Preheat oven to 425°F. Line a baking sheet with parchment paper and set aside.
In a medium saucepan, heat butter, milk, water, sugar and salt until butter is melted. Bring to a boil then reduce heat to low. Add flour and stir vigorously with a wooden spoon until mixture forms a ball and pulls away from the pan, about 2 minutes.
Remove from heat and beat in sweet potato puree until combine. Add eggs, one at a time, beating until dough is smooth and combined (it will look separated at first).
Transfer dough to a pastry bag fitted with ½-inch wide round tip. Pipe 1-inch balls, about 2-inches apart, on the prepared baking sheets. Wet your finger and smooth the top of each ball.
Bake 10 minutes, then reduce heat to 325°F and bake another 15-17 minutes, or until crisp, airy and golden brown. Use a paring knife to cut a small slit in the side of each puff to let steam escape. Cool completely.
Brown Sugar Marshmallow Crème
Fill a medium saucepan with a few inches of water and bring to a gentle simmer. Place egg whites, brown sugar and cream of tartar in a medium heatproof bowl and set over the simmering water. Don’t let it touch the water.
Cook, whisking constantly, until sugar is completely dissolved and the mixture reaches 160°F with an instant read thermometer, about 5 minutes. Remove from heat and mix in vanilla.
Transfer mixture to a stand mixer fitted with a whisk attachment and beat on high speed until peaks are stiff and glossy, 5-7 minutes. Transfer to a piping bag fitted with a large star tip.
To assemble puffs, use a serrated knife to slice off the upper ⅓ of the puff to create a lid and bottom. Pipe a swirl of marshmallow crème onto the bottom and use a handheld torch to lightly toast the marshmallow. Place the lid on top and gently press into place. Repeat filling remaining puffs. Serve.