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Chocolate Marshmallow Cake — The Dessert That Holds Twenty Together

Thanksgiving 2030. Twenty people. The table holds twenty now — two decades of Thanksgivings that started with six people in a house in the Lower Valley and now require Diego's folding tables and Sofia's catering spreadsheet and Camila's three-minute sung grace (year fifteen) and the particular abundance of a family that multiplies: children, grandchildren, in-laws, employees, friends, the community that Rosa's recipes gathered. I made the full spread for twenty. The flan was Rosa's. The turkey was Diego's. The tamales were Andrea's and Lupita's. The cornbread was Sarah's. The table was everyone's. And the everyone is the Thanksgiving.

The flan was Rosa’s — it always will be — but twenty people need more than one dessert, and this Chocolate Marshmallow Cake is what I brought to fill the rest of the table. It’s the kind of recipe that doesn’t ask too much of you when you’re already coordinating tamales and cornbread and Diego’s turkey, and yet it lands with the weight of something special, the kind of thing people remember alongside the grace and the folding tables. When the abundance is the point, this cake belongs on the spread.

Chocolate Marshmallow Cake

Prep Time: 25 min | Cook Time: 35 min | Total Time: 1 hr | Servings: 20

Ingredients

  • 2 cups all-purpose flour
  • 2 cups granulated sugar
  • 1 tsp baking soda
  • 1/2 tsp salt
  • 1 cup (2 sticks) unsalted butter
  • 1 cup water
  • 1/3 cup unsweetened cocoa powder
  • 2 large eggs, lightly beaten
  • 1/2 cup buttermilk
  • 1 tsp vanilla extract
  • 3 cups miniature marshmallows
  • Chocolate Frosting:
  • 1/2 cup (1 stick) unsalted butter
  • 1/3 cup unsweetened cocoa powder
  • 1/3 cup whole milk
  • 3 1/2 cups powdered sugar, sifted
  • 1 tsp vanilla extract
  • 1 cup chopped pecans or walnuts (optional)

Instructions

  1. Preheat and prep. Heat oven to 350°F. Grease and flour a 13x18-inch rimmed baking sheet (half-sheet pan) to yield generous portions for a crowd.
  2. Combine dry ingredients. In a large bowl, whisk together flour, sugar, baking soda, and salt. Set aside.
  3. Make the cocoa mixture. In a medium saucepan over medium heat, combine butter, water, and cocoa powder. Stir constantly until butter melts and mixture comes just to a boil. Remove from heat.
  4. Mix the batter. Pour the hot cocoa mixture over the flour mixture and stir until combined. Add eggs, buttermilk, and vanilla; stir until the batter is smooth and uniform.
  5. Bake. Pour batter into the prepared pan and spread evenly. Bake 28–32 minutes, or until a toothpick inserted in the center comes out clean.
  6. Add marshmallows. Remove the cake from the oven and immediately scatter miniature marshmallows evenly over the top. Return to the oven for 2–3 minutes, just until marshmallows are puffed and beginning to melt. Watch closely — they go fast.
  7. Make the frosting. While the cake rests, melt butter in a saucepan over medium heat. Stir in cocoa and milk; bring just to a simmer, then remove from heat. Whisk in powdered sugar and vanilla until smooth and glossy.
  8. Frost and finish. Pour the warm frosting over the marshmallow-topped cake and spread gently with an offset spatula. Sprinkle with nuts if using. Let the cake cool to room temperature — at least 30 minutes — before slicing into squares.

Nutrition (per serving)

Calories: 390 | Protein: 4g | Fat: 16g | Carbs: 60g | Fiber: 1g | Sodium: 180mg

How Would You Spin It?

Put your own twist on this recipe — what would you add, remove, or swap?