Gluten-Free Vegan Vanilla Cake

By Sara McGlothlin

Baking a Healthified birthday cake is one of my favorite things. My husband’s birthday falls just two weeks after mine, so when I asked what kind of cake he wanted, he replied “the normal birthday cake kind.” While I tend to choose something a little more specific, I interpreted that as “vanilla.” He would be good with the mix from the box, but since I care about his blood sugar just as much as I do my own, I still opted to bake a gluten-free, vegan variation, keeping it low-glycemic of course. Plus, he will eat whatever I make him!

Boston Cream Pie {Gluten-Free, Grain-Free}

Moist, creamy, chocolatey, and delicious! What more could you ask for in a dessert? A vanilla custard sits between two almond flour cakes then topped with a rich chocolate frosting. Grain-free.
Prep Time 1 hour 20 minutes
Cook Time 30 minutes
Passive Time 2 hours
Total Time 3 hours 50 minutes
Course Dessert
Servings 12 servings


  • 2 (8-inch) round springform cake pans
  • hand mixer or stand mixer
  • Mixing bowls
  • Small saucepan


For the cake

  • 3 cups almond flour
  • 3/4 cup coconut sugar
  • 1 teaspoon baking powder
  • 1/2 teaspoon baking soda
  • 1/4 teaspoon sea salt
  • 1/3 cup coconut nectar or maple syrup
  • 1/3 cup unsweetened applesauce
  • 3 eggs, beaten
  • 1 teaspoon vanilla extract

For the vanilla custard

  • 1 cup coconut cream* see note
  • 1 tablespoon gelatin I used Vital Proteins brand
  • 3 egg yolks
  • 1/3 cup powdered erythritol sweetener like powdered monk fruit or use powdered sugar
  • 3 tablespoons unsalted grass-fed butter cut into pieces
  • 2 teaspoons vanilla extract
  • 1 teaspoon arrowroot starch

For the chocolate frosting

  • 3/4 cup coconut oil room temperature
  • 3/4 cup grass-fed butter, vegan butter, or palm oil shortening room temperature
  • 1/2 cup raw cacao powder or cocoa powder
  • 1/2 cup powdered erythritol sweetener like powdered monk fruit or use powdered sugar
  • 1/4 cup arrowroot starch or tapioca flour
  • 1 teaspoon vanilla extract


  • Make the cake. Preheat the oven to 350°F. Spray 2 (8-inch) round springform cake pans with cooking spray.
  • In a large bowl or stand mixer, mix the almond flour, baking powder, baking soda, and salt. Stir to blend.
  • In a separate medium bowl, whisk together the eggs, applesauce, coconut nectar or maple syrup, and vanilla.
  • Pour the wet ingredients into the bowl with the flour mixture and beat until a batter is formed.
  • Evenly distribute the batter between the prepared cake pans, smoothing on top with a spatula until it reaches the sides. Bake for 25 to 30 minutes until a toothpick inserted into the center comes out clean. Allow the cakes to completely cool in the cake pans before incorporating the custard and frosting.
  • Make the custard. In a small saucepan over medium heat, slightly warm the coconut cream, about 1 minute. Add the gelatin and whisk vigorously until dissolved. Bring to a simmer. If there are still clumps, that is OK, they should dissolve eventually. 
  • Meanwhile, whisk together the egg yolks and powdered sugar. Once the coconut cream and gelatin mixture is simmering, add half to the yolk and sugar mixture and whisk to combine. Pour it back into the saucepan and whisk until everything is creamy. Continue to cook until slightly reduced, whisking constantly, about 4 minutes. Be sure to watch the saucepan, the mixture can heat quickly and the egg can curdle.
  • Remove from heat and whisk in the butter and vanilla extract. Add the arrowroot starch and whisk vigorously until dissolved. Alternatively, if there are still clumps, you can transfer the mixture to a blender and process until smooth. Transfer the mixture to a small glass or ceramic bowl. Allow to cool about 1 hour until thickened, stirring occasionally (**see note). Use immediately. 
  • To make the frosting, combine the coconut oil and butter (or vegan butter or palm oil shortening) in a large bowl. Beat with a hand mixer or immersion blender with the whisk tool until fluffy, about 1 minute.
  • Add the cacao powder or cocoa powder, powdered sweetener, arrowroot starch or tapioca flour and vanilla extract and beat again until everything is combined. Use a spatula to scrape down the sides as you need to.
  • Using a spatula, mix the frosting. Once ready to compile everything together, spread the vanilla custard evenly between the two cakes. Frost the cooled top cake, spreading the frosting evenly to the sides.


*Coconut cream is the milk solid that occurs at the top when you open a can of full-fat coconut milk. You can also purchase cans of coconut cream. I used two cans of coconut milk from room temperature to get the full cup of coconut cream, and then used the remaining liquid for smoothies! 
**Once cooling in the glass bowl, the custard remains slightly runny until about minute 0:45 – 0:50, and then thickens quickly. Continue to stir until it reaches this point to prevent a “skin” from forming on the surface.
Storage: Store the frosted cake in a cake keeper at room temperature for up to 3 days or in the refrigerator for up to 5 days. Refrigeration will alter the density of both the custard and the frosting, so this cake is best enjoyed on the same day or next day. 
Prep Tip: I suggest making the cake and frosting a day in advance, and then the custard on the day when you are ready to eat/serve.
Keyword Gluten-free, Grain-free

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