Vanilla Mochi Strawberry Mousse Rainbow Dream Cake

This bright and cheery spring cake was an act of storytelling, care, and a little bit of magic. I took a friend’s fleeting dream and turned it into something tangible, tasty, and full of memories. That’s not ordinary generosity. It's artistry mixed with intuition.

The dream my girl shared with me:

“I had a nap and I dreamt that you and I made a cake together it was a really simply vanilla bean fluffy cake with strawberry jam layers and rainbow confetti but like really pretty whimsical pastel confetti not generic rainbow confetti and it wasn't all confetti shaped it had stars and the whole time a very goth violinist was playing classical violin on a stool in the corner of the room so we gave them a slice.”

Thus, I created her a Vanilla Mochi Strawberry Mousse Rainbow Dream Cake!

It sounds like it belongs in a bakery with a line out the door. Four layers of soft vanilla, homemade mousse, buttercream, and pastel sprinkles. It’s whimsical, nostalgic, and deeply personal all at once. I wanted this cake to make her feel seen and heard, as well as to smile and feel joy. In fact, this cake for Mads is a love letter to whimsy, friendship, and the simple joy of surprising someone with sweetness.

About the cake:
Butter mochi is a staple at almost any party in Hawaii, and it’s easy to see why. The coconut custard glutinous rice cake is perfectly chewy, slightly sticky, and just dense enough, with a hint of vanilla and salt. For my version, I added extra flour and sugar, along with a touch more baking powder, to create MORE cake, but also a bit more bounce and vanilla dream.

About the mousse:
If you can believe it, in all my years of cooking and baking, I’ve never made a traditional mousse. This was surprisingly easy – and I left it UNSTRAINED so that we could taste the fresh, chunky, seasonal strawberry slices inside the silky mousse.

About the buttercream:
While buttercream is a pain to make, this time it turned out perfectly. The photos may not do justice, but the icing was impeccably smooth, impeccably sweetened, and absolutely gorgeous in form and flavor – seamless in every way.

Vanilla Mochi Strawberry Mousse Rainbow Dream Cake

Vanilla Mochi Cake:

butter or oil + parchment paper to grease and line four 6” cake pans
8 Tbs. butter, melted
2 ¼ cup glutinous rice flour (mochiko flour)
1 cup all-purpose flour
1 ½ cups granulated sugar
1 Tbs. baking powder
1 tsp. kosher salt
1 cup heavy cream
1 cup full-fat coconut milk
4 large eggs
2 tsp. vanilla extract
½ cup coconut flour

Preheat the oven to 350°F.

Grease the pans with butter or oil and line with parchment paper.

Combine the mochiko, sugar, baking powder, and salt in a large bowl. Whisk to combine.

In a separate bowl, combine the milk, coconut milk, eggs, and vanilla, whisking to combine.

Combine the two bowls of ingredients together in the large bowl of a stand mixture, along with the melted butter. Fold in the coconut flour.

Mix until fluffy and smooth.

Divide the mixture among the four prepared pans and bake for 30-35 minutes, until golden brown and a toothpick inserted comes out clean.

Cool for 15 minutes before inverting, releasing from pans, and cooling for several hours. Wrap tightly in plastic wrap and chill for 4-8 hours, or overnight (freeze for up to 2 weeks, if desired).

 

Strawberry Mousse:

1 pkg. unflavored gelatin
¼ cup cool water
12 oz. frozen strawberries, thawed
½ cup granulated sugar
1 cup whipping cream
½ tsp. vanilla extract

Chill the bowl and whisk of a stand mixer in the fridge for several hours.

Sprinkle the gelatin over the ¼ cup of water in a small bowl. Allow to bloom for five minutes.

In a small pot, combine the strawberries and sugar, warming on low to medium heat until the sugar has dissolved and the strawberries are mostly broken down. Stir constantly.

Remove from heat and cool for 10-15 minutes. 

Add the bloomed gelatin and mix well.

Cool the strawberry gelatin mixture on the counter for several hours.

In the chilled mixing bowl, whip the cream on medium-high, until soft peaks form.

Add the vanilla and continue to beat for another 1-2 minutes.

Fold in the cooled gelatin.

Remove the cakes from the fridge or freezer.

 

Place on a cardboard base and a cake stand.

 

Slather ¼ of the mousse over the first layer of cake (secured to the cake board with 1 Tbs. of mousse). Top with the second layer of cake and repeat until the last layer has been slathered and any remaining mousse coats the outside of the tiered cake to lock in all the moisture.

 

Chill for several hours. 

 

Meanwhile, prepare the buttercream.

 

Vanilla Buttercream:

 

1 lbs. salted butter, room temperature

3 Tbs. heavy cream

4 cups powdered sugar
1 tsp. vanilla extract

 

Using a stand mixer, cream the butter for 15-20 minutes. Drizzle in the cream and continue to mix for several minutes. Add the powdered sugar in batches of ½ cup at a time. Drizzle in the vanilla. Beat until smooth and creamy.

 

Remove the mousse filled cake tiers from the fridge and ice the cake with the buttercream, until completely smooth on all sides.

 

Topping and Décor:

 

rainbow pastel sprinkles and shapes

 

Sprinkle and press all the candy décor into the tops and sides of the cake. Be sure to spill the sprinkles (and powdered sugar from the buttercream) ALL over the counter and floor, just like I did 🤦🏼‍♀️ - such a mess! 😂🤣😂🤣😂🤣😂!!!

Top with fresh flowers for spring and summer décor, if desired.

Enjoy your dream cake!