Ube Cake

Ube cake is a traditional Filipino dessert using ube, or purple yam. This beautiful naturally violet-hued sweet potato is used frequently in Filipino cuisine and comes in many other forms like dehydrated powder, frozen pulp, and extract. The cake itself is generally either a chiffon or sponge and made into cupcakes, layered cakes, or Swiss roll style and then filled or smothered with a healthy dose of buttercream.

Ube pairs wonderfully with coconut, so my cake is more of a traditional style cake using butter, coconut milk, and ube extract for easier sourcing. I then layer it with my Italian buttercream and macapuno strings, delicious jelly-like coconut strips found in young coconut seeds, which add a sensational mouthfeel in contrast to the tender cake and silky buttercream. See my article on how to frost a cake if you are new to this process.

“The light, fluffy buttercream and coconut strings complement this vibrant cake so well. Unlike many three-layer cakes, this one seemed quicker to assemble due to the fact that you freeze the layers before frosting, which really sped up the process and helped reduce crumbs.” —Julia Hartbeck

A Note From Our Recipe Tester

Ingredients

For the Cake:

Cooking spray
12 ounces (1 1/2 cups) unsalted butter, room temperature
3 1/4 cups (650 grams) granulated sugar
3 3/4 cups (505 grams) cake flour, sifted
1 tablespoon baking powder
1 teaspoon fine salt
5 large eggs
1 tablespoon ube extract
1 1/4 cups full-fat coconut milk

For the Italian Buttercream:

2 cups (1 pound) unsalted butter, cut into small cubes
1 1/2 cups (300 grams) plus 1/3 cup (65 grams) granulated sugar, divided
1/2 cup water
7 large egg whites
1/4 teaspoon fine salt
1 teaspoon vanilla extract

For Assembly:

1 cup coconut sport macapuno strings, more for garnish, optional

Steps to Make It

Note: While there are multiple steps to this recipe, this ube cake is broken down into workable categories to help you better plan for preparation.

Make the Cake

Gather the ingredients.

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Position a rack in the upper and lower third of the oven and heat to 350 F. Cut three 8-inch parchment circles by tracing the bottom of a cake pan onto a piece of parchment paper.

Spray three 8-inch cake pans with cooking spray and place one circle of parchment at the bottom of each pan.

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In a stand mixer fitted with the paddle attachment, cream together the butter and sugar on medium speed until light and fluffy, about 2 minutes.

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In a large bowl whisk together the sifted cake flour, baking powder, and salt. Set aside.

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Once the butter and sugar have fully creamed, turn off the mixer and scrape down the sides of the bowl. Turn it back to medium speed and add the eggs one at a time. Turn the mixer off, scrape down the sides of the bowl. Add the ube extract and paddle again until completely combined.

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Turn the mixer off, scrape down the sides and add about 1/3 of the dry ingredients. Mix on low until almost combined.

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Keeping the mixer on low speed, slowly drizzle in about half of the coconut milk. Continue to alternate the wet and dry ingredients until everything is finished, ending with the dry ingredients. Scrape down the sides of the bowl and paddle again for about 10 seconds just to make sure everything is fully incorporated.

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Divide the batter evenly among the three cake pans and smooth out the tops. Bake until the cake pulls away from the sides and springs back to the touch, 30 to 40 minutes, rotating the pans in the oven halfway through baking (begin checking the cakes for doneness at about 25 minutes).

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Let the cakes sit at room temperature until completely cool, about 1 hour. Use a paring knife around each of the cakes to loosen the sides.

Pull out a long piece of plastic wrap onto your work surface, flip the cake upside down onto the plastic wrap. Peel off and discard the parchment paper. Wrap the cake layer and put it into the freezer. Repeat with the other 2 layers, freezing them all flat for at least 1 hour.

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Make the Italian Buttercream

Gather the ingredients.

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Let the butter come to room temperature.

Meanwhile, put 1 1/2 cups of the granulated sugar in a small saucepan. Add the water and stir to combine. With your fingers or a pastry brush, wipe any sugar crystals from the sides of the saucepan.

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Heat over medium-high heat, undisturbed, until the sugar syrup reaches 238 F, about 10 minutes (do not stir the syrup while it is cooking since this can cause the sugar to crystallize). Remove from the heat.

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Meanwhile, put the egg whites and salt into the bowl of a stand mixer fitted with the whisk attachment. Whisk on medium speed until the whites become frothy.

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With the mixer running, add the remaining 1/3 cup granulated sugar in a slow steady stream. Increase the speed to high and continue to whisk until the mixture reaches medium-stiff peaks.

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Reduce the mixer speed to low. With the mixer running, slowly stream the sugar syrup down the side of the bowl until fully incorporated into the meringue.

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Increase the speed to medium-high, and continue to whisk until the meringue is doubled in size and the bottom of the bowl is no longer warm, about 10 minutes.

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Switch to the paddle attachment. With the mixer on medium speed, slowly add the cubed butter a couple pieces at a time until the butter is fully incorporated, smooth, and fluffy before adding the next pieces. The mixture may seem to resemble the texture of cottage cheese or thin out at moments as you add the butter, but continue to beat the mixture and it will begin to thicken to smooth, firm peaks.

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Add the vanilla, continuing to mix until everything comes together into a beautiful silky smooth buttercream.

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Assemble the Cake

Drain the macapuno strings with a mesh sieve, if using.

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Remove the cakes from the freezer. Place one cake on a cake board or serving platter on top of your cake turntable. Using a serrated knife slice off any dome the cake may have to make a flat layer. Save the scraps for a snack or to make cake pops. Slice the tops off the remaining 2 cakes.

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Spread some buttercream on top of the bottom layer, smooth it out with an offset spatula, and arrange half the macapuno strings over the buttercream.

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Top with a second layer of cake, some more buttercream, and the remaining macapuno strings.

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Top with the final layer of cake and press down to secure.

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Top with a generous amount of buttercream and use a large offset spatula to smooth out the top while spinning the turntable. Push any excess buttercream that goes over the edge of the top onto the sides.

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Spread some more buttercream around the sides of the cake and holding your offset spatula vertically, smooth it out into a very thin layer while spinning the table to make a crumb coat. Place the cake in the fridge for about 5 minutes to set up.

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Finish the cake with a final layer of buttercream. Garnish with more macapuno strings, if desired. Serve.

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Tips

The cake is best served at room temperature.
You can add more or less ube extract based on your color and/or taste preference.
If the buttercream is soupy, either the meringue was too warm before adding in the butter, or you just need to whip it longer. If whipping it longer is not working, try putting the whole bowl in the fridge for 15 minutes to chill, then scrape down the sides, and whip again.
If the buttercream is chunky, the ingredients were too cold. Let it come to room temperature for 15 to 30 minutes and try whipping again.

How to Store and Freeze

Ube cake can be stored at cool room temperature for up to three days in a case or airtight container; up to one week in the fridge wrapped in plastic or in an airtight container; or up to six months in the freezer.

Can I Make The Cake and Buttercream in Advance?

The cake layers can be made in advance and frozen for up to 3 months.
The buttercream can be made in advance and refrigerated for up to 1 week or frozen for up to 3 months until needed, but it needs to be brought back to room temperature and paddled again until smooth before using.