Purple Sweet Potato Bars with Homemade Marshmallows

Purple sweet potatoes not only give these bars a colorful hue but a taste and texture that pair perfectly with their toasted marshmallow top.


  • For the marshmallows:
  • 1 cup water, divided
  • 3 tablespoons gelatin
  • 1 cup plus 2 tablespoons honey
  • 1 teaspoon vanilla extract
  • For the filling:
  • 3 pounds purple sweet potatoes, baked until tender, peeled
  • 12 tablespoons butter, softened at room temperature
  • 5 large eggs
  • 1 cup sugar
  • 3 cups evaporated milk
  • 1 tablespoon cinnamon
  • 1 1/2 teaspoons nutmeg
  • 1 tablespoon salt
  • 1 tablespoon vanilla extract
  • 4 tablespoons lemon juice
  • For the crust:
  • 60 gingersnap cookies
  • 2 tablespoons brown sugar
  • 6 tablespoons butter, melted
  • 1/2 teaspoon salt


  1. Make the crust: Preheat the oven to 350 degrees. Line a 9 by 12-inch pan with baking spray and parchment paper. Set aside.
  2. In the bowl of a food processor fitted with the blade attachment, pulse gingersnaps until they resemble coarse sand. Pulse in brown sugar, salt and butter and mix to combine. Press into prepared pan and bake for 10 to 12 minutes until fragrant.
  3. Make the filling: In the bowl of a food processor fitted with the blade attachment, add potatoes, eggs, butter, sugar and evaporated milk and mix until smooth. Add cinnamon, nutmeg, salt, lemon and vanilla and mix until combined.
  4. Make the marshmallows: Pour 1/2 cup water into the bowl of a stand mixer and sprinkle gelatin over top. Set aside.
  5. Add honey and remaining 1/2 cup water to a medium saucepan over medium heat. Bring to a boil, then reduce heat and simmer until it reaches the soft ball stage or a candy thermometer reads 240 degrees.
  6. Fit the mixer with the whisk attachment, then turn it on low and beat gelatin mixture. With mixer running, carefully pour in honey syrup in a slow, continuous stream. Add vanilla extract, turn mixer to high, and beat for 10 minutes, until white, glossy peaks form and mixing bowl feels cool to the touch. Keep mixer running on low to keep mixture from setting.
  7. Make the bars: Pour the sweet potato mixture into set bar bottoms and bake for 35 to 40 minutes until filling is firm but a little wobbly. Let cool for up to an hour. Top with marshmallows and gently toast with a torch until golden. Cut and serve. Bars are best eaten the same day.