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This Gender Reveal Cake decorated with the watercolor technique has a fun surprise sprinkle center! It’s made with layers of colored vanilla cake, sandwiched with vanilla buttercream and filled with sprinkles and candies for a sweet surprise.
A few months ago, I had the pleasure of creating a gender reveal cake for a close friend of mine. She had planned a lovely celebration during which we would all find out the sex of a baby!
Well, everyone but me. As the cake baker, I was the first to learn the baby’s gender. I’ll be honest, I was quite nervous being the only person who knew the gender of the baby because I was afraid of getting it wrong! Thankfully, her doctor has actually sent an email, which meant that I could refer to it, and make sure I didn’t make a mistake!
All about this Gender Reveal Watercolor Surprise Cake
The Cake
Since the cake was going to be colored, the cake layers are a classic vanilla cake.
It’s my favorite vanilla cake recipe, which I also used in this fault line cake, Nothing too fancy, but it’s a really moist cake, with ingredients like sour cream, oil and butter. It all makes a difference!
You can find my recipe below, or use your favorite vanilla cake!
I add just a couple of drops of Americolor Soft Gel Paste Colors in the color blue!
The Filling & Surprise Centre
The cake layers have generous amounts of vanilla Swiss Meringue Buttercream. My recipe is below!
For the surprise center, you can use any combination of candy and sprinkles in the color you want. Using different shapes and sizes creates the best effect! I used blue and white sprinkles, blue M&Ms, and some other blue and white candies I found at Bulk Barn!
You can even order M&M’s in blue or pink right from their website!

The Frosting
The Frosting is just a simple vanilla Swiss Meringue Buttercream.
You can of course easily use any other type of buttercream, such as Italian or American, as well to get the same look!

Decorating the Gender Reveal Cake
Step #1: Stack & Fill the cake
This cake had four cake layers.
Once the cake layers are baked and cooled completely, you’re ready to stack and fill the cake. I like to bake my cake layers a day in advance and then stick them in the fridge so that they are cold to the touch, and are easy to work with.
Step #2: Creating the surprise centre
You’ll have to carve a circle in the center of two of the cake layers for the surprise center.
I used a 3-inch circle cookie cutter, but you can easily use a lid, or even cut a circle in the center, freehand using a sharp knife!
Try as much as you can to make sure the circles are in the middle of the cake layers, and that they align when the cake layers are stacked on top of one another.
Once you stack the first three layers, fill the center with the candies you have. I have additional tips below, and a detailed tutorial in the recipe!
Tip: If your cake layers break when stacking the cake, just fix them by using buttercream as a glue.

Step #2: Crumb Coat and Chill
After the cake is stacked and leveled, apply a thin crumb coat, and let it chill in the fridge for at least 30 minutes, until the buttercream is firm to touch.
I use Swiss meringue buttercream so it never forms a crust, but if you use American buttercream, it would develop a sort of crust.
Step #3: Final Buttercream Coat
Once the cake has had time to chill, it’s time to decorate.
Apply buttercream and keep smoothing with a bench scraper or offset spatula until you are happy with the look!
Always make sure to start with more buttercream than you need!
Chill the cake for 30 minutes.

Step #4: The Watercolor Effect
While the cake is in the fridge, make the blue and pink icing for the outside of the cake.
Once the cake has chilled for at least 30 minutes, and the buttercream is firm to the touch, start decorating.
Using an offset spatula, spread alternating blobs of blue and pink frosting.
Smooth gently with the bench scraper.
Wipe the scraper after each swipe (to avoid mixing colors), until the desired look is achieved.
Step #5: Finishing Details
Fill a piping bag fit with a 1M tip with white Swiss meringue buttercream.
Pipe swirls on the top of the cake.
Finish decorating the sides with some edible gold leaf – like this one from SloFood Group for an optional sparkle!
And Voila! All done with the Gender Reveal Watercolor Surprise Cake!

A Few Tips:
- Cake: recipe makes four 8-inch layers.
- Cake Color: Make sure to mix a little more color than you think you need, so that the colors are noticeable after baking.
- Buttercream: I use a Swiss Meringue Buttercream, but you can easily substitute with American or Italian if you prefer!
- Carving the cake: The cake cavity doesn’t need to be too big. The bigger the circle, the more delicate the cake will be to handle. A three-inch circle was enough for an 8-inch cake!
- Filling the cake: Before filling the candies and sprinkles into the cake, make sure to allow the buttercream to firm up a bit, otherwise, the candies will not flow out as intended.
- Filling the cake: Make sure to fill the cake cavity completely. It’ll help stabilize the top of the cake, which might sink if there not enough support, and too much space.
- Stacking the cake: Keep the flattest cake layer for the top of the cake. This way there the top of the cake looks sharp.

Follow me on Instagram @sprinklesandscribbles for more baking inspiration!
Cheers,

Ready to make this Gender Reveal Watercolor Surprise Cake?
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Gender Reveal Watercolor Cake with Surprise Centre
Ingredients
Vanilla Cake
- 360 grams all-purpose flour 3 cups
- 400 grams granulated sugar 2 cups
- 120 grams room temperature unsalted butter
- 1 tsp baking soda
- 1 tsp salt
- 3 tsp baking powder
- 1/2 cup canola oil
- 4 large eggs
- 180 grams sour cream
- 2 tbsp pure vanilla extract
- 1/2 cup water
Vanilla Swiss Meringue Buttercream
- 360 grams about 12 large egg whites
- 720 grams granulated sugar
- 900 grams unsalted butter room temperature cubed
- 2 tsp vanilla
Assembly
- 1/3 cup Blue or Pink Candies depending on the gender
- Gel food coloring Blue and pink
Instructions
- Instructions
Vanilla cake
- Preheat oven to 350F and grease and flour four 8” cake rounds.
- Whisk together flour, sugar, baking soda, salt, and baking powder in a bowl.
- Add butter, and beat well with a hand mixer or in a stand mixer with the whisk attachment, until the mixture resembles fine crumbs.
- In a separate bowl, whisk together egg, sour cream, vanilla, and oil until combined.
- Pour wet ingredients into the flour and butter mixture, and beat on medium for 3-4 minutes. The mixture will be dry at this point.
- Add in water and mix until just combined. Fold in the crushed Oreos. Do not overmix.
- Spread batter evenly into prepared pans. Smooth the tops with a spatula.
- Bake for approx. 20-25 mins or until a toothpick inserted into the center comes out mostly clean. Place cakes on a wire rack to cool for 20 mins then turn out onto wire rack to cool completely before removing from pan.
Vanilla Swiss Meringue Buttercream
- Place egg whites and sugar into the bowl of a stand mixer, whisk until combined. Place the bowl over a hot water bath on the stove and whisk constantly until the mixture is hot and no longer grainy to the touch or until it reaches a temperature of 165 degrees F on a candy thermometer. Place the bowl on your stand mixer and whisk on medium-high until the meringue is stiff and cooled (the bowl is no longer warm to the touch (approx. 5-10mins)). Switch to a paddle attachment. Slowly add cubed butter and mix until smooth. Add vanilla and continue to whip until smooth.
Cake Assembly
- Spread some buttercream on the cake board.
- Place one layer of cake on a cake board and place it in the fridge for 5-10 minutes. This will help the cake stick to the cake board and not slip as you stack and frost.
- In the meantime, carve out circles in the middle of 2 of the cake layers for the candy filling
- Remove from the cake and cake board from the fridge.
- Top with approximately 1/3 cup of frosting and spread evenly.
- Add one of the cake layers with the holes on top. Top with buttercream and spread evenly.
- Repeat with the next cake layer.
- Spread a thin layer of buttercream on the inside of the cake, to crumb coat where you will be filling the candy.
- Place the cake in the fridge for 5-10 minutes.
- While the cake is chilling, prepare the candies as required.
- Remove cake from the fridge and fill the cavity with the prepared candies, and sprinkles. Fill the cavity completely without overfilling it.
- Finish stacking the cake – Top with approximately 1/3 cup of frosting and spread evenly, then stack the final layer to hide the candy surprise.
- Apply a thin coat of frosting all over the cake for the crumb coat.
- Place cake in the fridge for 30 minutes.
- Apply final base layer of white buttercream. Smooth as needed. Chill again for 30 minutes again.
- Prepare pink and blue frosting – about 1/4 cup each.
- Remove chilled cake.
- Using an offset spatula, spread alternating blobs of blue and pink frosting.
- Smooth gently with the bench scraper, wiping the scraper after each swipe, until desired look is achieved.
- Fill a piping bag fitted with a 1M tip, with white vanilla Swiss Meringue Buttercream.
- Create swirls on the top of the cake to finish the look.
- Enjoy!
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