It is morning. You open your eyes, and for the first few seconds, everything looks unfamiliar. You are not at home. The room tilts slightly to the left and you hear a creaking wooden sound and water beneath you. Ah yes! You are on a private boat in the middle of the caribbean. It is summertime and you are on vacation. You took off work and your only responsibilities are to relax and enjoy the scenery. Everyone is still asleep so you make your way outside for some fresh tropical morning air. You quietly open the sliding glass door and are instantly greeted with a cool, salty ocean breeze while the warmth of the rising sun caresses your face. The sounds of water gently splashing against the sides of the boat and the pleasant rocking puts you in a meditative state and everything feels just perfect in that dreamy summer moment. It is just you, a glowing sun, a deep blue ocean, and a comfortable breeze that cleanses your mind and body from all the nonsense that clutters it from day to day. We look forward to vacations like these for good reason: they allow us to escape our daily reality and experience new sights, sounds and flavors. Of course it would be wonderful if we could just pack up and head to the tropics whenever we want, but this is not always possible for everyone. But there are things we can do to make up for it. And this coconut mojito cake is one of them.
This extraordinary cake comes from Tessa Huff’s gorgeous new book, Layered. Filled with beautifully photographed and deliciously innovative recipes, her cookbook also has a variety of decorating techniques with easy-to-follow instructions. We must admit though, Tessa does make one thing difficult… choosing which recipe to make first! Everything looks exceptional, and with selections like cinnamon roll cake, orange passionfruit cake, and cookies ’n cream cake, our decision did not come quickly. After much consideration, this coconut mojito cake seemed like the perfect choice to welcome the new sunny season. Three layers of fluffy lime cake made with freshly grated lime zest are lightly brushed with a mint rum simple syrup that is cool and refreshing. Surrounded by a creamy coconut rum frosting, each layer of this pillowy cake is topped with a tangy lime filling: a smooth swiss meringue buttercream made with lime juice and lime zest. And it doesn’t stop there! This soft and decadent masterpiece is then topped with a homemade lime mint sugar that tastes just as you would imagine—a perfectly balanced mix of sweet, minty, and sour that also adds a cordial crunch. The combination of the refreshing citrus, sweet coconut, and mint flavors makes this the perfect choice for your sweet summer selections.
Baking a cake is always a fun project, and this recipe makes it easy to prepare at your own pace. All the components—the cake, frosting, filling, and garnish—can be made separately ahead of time and assembled whenever you are ready. The coconut frosting and lime filling can be made up to ten days in advance, and the festive lime mint sugar and the mint rum simple syrup will both keep fresh for a week. Even the cake layers can stay wrapped snugly in the fridge for up to three days. Of course, if you feel like making everything from start to finish all at once, that works too! With the aromas of freshly-grated lime zest, creamy coconut, white rum, and muddled mint filling the kitchen, this recipe is a pleasure to make, and from the very first taste, cool ocean breezes and warm caribbean sunshine will serenade your tastebuds. We may not be able to head to the tropics every weekend, but thankfully, we can always have cake.
Coconut Mojito Cake
adapted from Layered by Tessa Huff
makes one 6-inch three-layer cake, serves 8 to 10
For the lime mint sugar:
1/2 cup (100g) granulated sugar
1 tablespoon loosely packed chopped mint leaves
1 teaspoon finely grated lime zest (about 1 lime)
For the lime cake:
5 large egg whites
1 teaspoon vanilla extract
3/4 cup (180ml) whole milk, divided
2 1/2 cups (325g) cake flour
1 1/2 cups (300g) granulated sugar
1 tablespoon baking powder
3/4 teaspoon salt
1 1/2 tablespoons finely grated lime zest (about 3 to 4 limes)
3/4 cup (1 1/2 sticks / 170g) unsalted butter at room temperature, cubed
For the mint rum simple syrup:
1/2 cup (100g) granulated sugar
1/4 cup water
1/4 cup (60ml) white rum
1 cup (30g) loosely packed mint leaves
For the swiss meringue buttercream frosting:
1/2 cup plus 2 tablespoons (150ml) egg whites (about 4 large eggs)
1 1/4 cups (250g) granulated sugar
2 cups (4 sticks / 450g) unsalted butter at room temperature, cubed
2 teaspoons vanilla extract
For the lime filling:
2 ounces (55g) cream cheese, at room temperature
1 1/4 cups (300ml) swiss meringue buttercream frosting
2 teaspoons freshly-squeezed lime juice
1 teaspoon finely grated lime zest (about 1 lime)
green gel food coloring (optional)
For the coconut rum buttercream:
2 1/2 cups (600ml) swiss meringue buttercream frosting
1/4 cup (60ml) cream of coconut
1 1/2 tablespoons white rum
Make the lime mint sugar:
Combine the sugar, mint leaves, and lime zest in a food processor, and pulse until the mint is finely minced and the mixture is evenly blended. Spread the sugar on a piece of parchment paper and allow to dry overnight before using. The next day, transfer the sugar to a bowl and break up any clumps.
Make the lime cake:
Preheat oven to 350ºF. Butter and flour three 6-inch cake pans and set aside.
In a small bowl, combine the egg whites, vanilla, and 1/4 cup (60ml) of the milk, stir until blended, and set aside.
In the bowl of a stand mixer, sift the flour, sugar, baking powder, and salt together. Add the lime zest, and using the paddle attachment, mix on low until combined. Add the butter and the remaining 1/2 cup (120ml) of milk, and continue to mix on low until the ingredients are moistened. Raise the speed to medium-high and mix for 1 minute, until evenly combined. Stop the mixer, and scrape down the sides of the bowl. Turn the mixer back to medium speed, and add the egg white mixture a third at a time, mixing for about 20 seconds and scraping down the sides of the bowl between each addition.
Evenly divide the batter between the three prepared cake pans. Bake for 25 to 35 minutes, until a toothpick inserted in the center of a cake comes out clean. Let cool on a rack for 15 minutes, then remove the cakes from their pans and place on the rack to cool completely.
Make the mint rum simple syrup:
In a small saucepan, combine the sugar, water, and rum, and stir to combine. Bring to a boil over medium-high heat, stirring to dissolve the sugar. While the pan is heating, place the mint leaves in a bowl and muddle them to release their aroma. Once the sugar mixture is boiling, add the mint leaves and turn down to a gentle simmer. Cook for 10 minutes, until the liquid reduces to a syrup. Let cool completely in the pan, then pour the mixture into a bowl through a fine-mesh sieve, pressing the mint leaves to release all the syrup. Discard the mint leaves.
Make the swiss meringue buttercream frosting:
In the bowl of a stand mixer, combine the egg whites and sugar. Whisk briefly to combine. Fill a medium saucepan with a few inches of water, then place the mixing bowl on top of the pan to create a double boiler. The bottom of the bowl should not touch the water, so pour some water out if it does. Place the pan on the stove on medium-high heat, and cook, whisking occasionally, until the mixture reaches 160ºF/70ºC on a candy thermometer (if you do not have a thermometer, simply heat until the mixture is hot to the touch). Once the correct temperature is reached, remove the mixing bowl from the pan and set it onto the stand mixer.
Using the whisk attachment, beat the mixture on high speed until the outside of the bowl is completely cool to the touch, and the mixture is smooth and holds stiff peaks, about 10 to 15 minutes. Once completely cool, stop the mixer and swap in the paddle attachment. Turn the mixer to low speed, and add the butter a few tablespoons at a time. Once all the butter is added, add the vanilla. Raise the speed to medium-high and beat until the frosting is smooth and creamy, about 5 minutes. Transfer the frosting to a bowl, and wipe off the mixing bowl and paddle.
Make the lime filling:
Place the cream cheese in the wiped-out mixing bowl, and use the paddle attachment on medium speed to beat it until creamy. Add 1 1/4 cups (300ml) of the buttercream frosting, the lime juice, zest, and optional food coloring, and mix until smooth and evenly blended. Transfer to a small bowl, and wipe off the mixing bowl and paddle.
Make the coconut rum buttercream:
Place 2 1/2 cups (600ml) of the buttercream frosting in the wiped-out mixing bowl, then add the cream of coconut and rum. Use the paddle attachment on medium speed to mix until blended and smooth.
Assemble the cake:
Once the cakes have cooled completely, use a serrated knife to level the tops. Generously brush the tops of the cakes with the mint rum simple syrup until they are evenly moistened (you will not use all the syrup). Place one layer on a serving plate, then top with half of the lime filling. Spread the filling evenly over the cake, then top with the second cake layer. Spread the remaining filling over the cake evenly, then top with the third cake layer. Frost the top and sides of the cake with the coconut rum buttercream, and sprinkle the lime mint sugar over the top.
To achieve the swirl effect, first frost the cake evenly and smoothly on the top and sides (this is easiest when using a turntable). Press the tip of a small spatula gently into the frosting at the base of the cake. Slowly turn the turntable and raise the spatula up the side of the cake, turning as you go, creating a swirl up the sides. For the top, do the same thing by starting at the edge and slowly turning the cake as you move the spatula towards the center, creating a spiral. Generously sprinkle the lime mint sugar in a circle around the top edge of the cake.
— Every component of this recipe can be made ahead of time, and stored until ready to assemble the cake. The lime mint sugar can be stored in a sealed container at room temperature for up to a week. The cake layers, once completely cooled, can be wrapped tightly in plastic wrap and refrigerated for up to 3 days. The mint rum simple syrup can be stored in an airtight container in the fridge for up to a week. The swiss meringue buttercream, lime filling, and coconut rum buttercream can all be made ahead of time and stored in the fridge for up to 10 days. Before using the buttercreams or filling, bring them to room temperature and beat them in the mixer until smooth. Don’t panic if the frosting seems to separate, just keep beating and it will come together.