First Birthday Smash Cake

Recipe by Sarah Jampel
Not Yet Reviewed

Babies will love tasting (and destroying) this smash cake for their first birthday. It’s soft enough for them to tear into with their little hands, yet sturdy enough to hold its shape during frosting and assembly. The best part? It’s made with simple ingredients and just a touch of sweetness. Quick to whip up and easily adaptable, this smash cake can be customized to suit your little one’s needs — see “tips,” below for details on how to make it dairy-free, use all-purpose flour, or swap applesauce for the bananas.  

Prep
20 mins
Bake
15 to 20 mins
Total
1 hr 20 mins
First Birthday Smash Cake on a plate - select to zoom
First Birthday Smash Cake on a plate - select to zoom
A baby attacking her First Birthday Smash Cake - select to zoom
First Birthday Smash Cake with a big bite taken out of it - select to zoom

Instructions

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  1. To make the cake: Preheat the oven to 350°F with a rack in the center. Line an 8" square pan with parchment, then lightly grease. 

  2. In a large bowl, whisk together the mashed banana, eggs, butter, syrup, and vanilla until well combined. Stir in the flours, baking powder, cinnamon, and salt until no dry patches remain. 

  3. Transfer the batter to the prepared pan and spread into an even layer.  

  4. Bake for 15 to 20 minutes, until the cake is golden brown on the edges and the entire surface looks matte. 

  5. Remove the pan from the oven and let the cake cool in the pan on a wire rack for about 15 minutes. Transfer the cake directly to the wire rack to cool completely. (The cooled cake can be wrapped in plastic and stored in the freezer for up to 2 months at this point. Defrost in the refrigerator overnight before proceeding with the recipe.)

  6. To make the whipped cream frosting: In the bowl of a stand mixer fitted with the whisk attachment, whip the cream, yogurt, syrup, and vanilla just until stiff peaks form. Set aside. 

  7. Use a 3 1/2" or 4" round cutter to cut three or four rounds from the cake layer. (If using a 4" cutter, you will have to piece together one of the layers from different sections of the cake.) 

  8. To assemble the smash cake: Spoon a small amount (about 1 teaspoon) of the whipped cream frosting on a serving plate, then place the first layer down on top of it (this helps the cake stay in place). Add a dollop of frosting (1 to 2 tablespoons) on top of the layer, then spread it evenly to the edges. Repeat the process, stacking the cake and adding frosting between each layer.  

  9. Once the cake is assembled, coat the outside in an even layer of frosting (a crumb coat). Transfer the cake to the refrigerator for about 20 minutes, until chilled.  

  10. Cover the cake with the remaining frosting. Decorate with sprinkles and/or fresh berries, as desired. 

  11. If not serving immediately, chill the smash cake until ready to serve (up to 1 hour in advance). 

Tips from our Bakers

  • The mashed banana can be substituted with 1 cup (227g) unsweetened applesauce. Increase the baking time to 20 to 25 minutes. 

  • For a dairy-free cake, use the vegetable oil (instead of the butter) and frost the cake with coconut whipped cream; we’ve included a recipe in our No-Bake Vegan Chocolate Pie.

  • Use 1 1/4 cups (150g) King Arthur Unbleached All-Purpose Flour in place of the almond and oat flours, if desired. No other adjustments are required. 

  • This recipe makes a great base for kid-friendly, snack-sized mini muffins. Prepare the batter as described and use a generous tablespoon or level tablespoon scoop to distribute the batter among the wells of a mini muffin pan. Bake at 350°F for 10 to 12 minutes, until a toothpick inserted into the center comes out clean. 

  • Be aware: Some of your baking ingredients can be a hidden source of gluten. Learn more at our blog post: For gluten-free baking, think beyond just flour. For additional information on King Arthur-produced products, read the complete details of our allergen program, including our contact-prevention practices.

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