On Friday I decided to make my 2nd bake of the chocolate week bake-along: A White Chocolate Celebration Cake. Since I had already made brownies and I knew that I would also be making a chocolate babka over the weekend, I decided to give away the cake instead of having more dessert for the four of us to eat. I put out a post on Facebook offering it to the first person that responded and could pick it up that evening and it was spoken for within 10 minutes!
How to make the white chocolate cake?
The contestants on the show were required to make a white chocolate layer cake that showcased white chocolate but could have other fillings or flavours as well. One of the judges commented on how they would have to modify the sponge cake recipe to accommodate for the extra fat added by the white chocolate so that it wouldn’t be too dense. One of the contestants watered down her white chocolate to balance this and was looked at askance by the judges for this. Her cake ended up undercooked, so it may have been due to the added water. Another contestant took a bit of a shortcut and made a coconut cake with chopped white chocolate in it.
I agonized for a bit about how to do the cake. Most of the recipes I found online actually used the watered down white chocolate method and others, including the one with the chopped chocolate from the show made 6-inch cakes, which I don’t have the right sized pans for. I needed something that would make 8-inch layers. I could have upped the amount for some of the recipes by 1.5 times to get the amount of batter needed, but that was a bit more complicated for the eggs, where I would end up needing 4.5 eggs.
I have a recipe in my Cook’s Illustrated cookbook for a coconut cake that would make the amount of batter I needed. I decided to use that and add extra shredded coconut and mini white chocolate chips for a cake that was similar to the one from one of the contestants that I talked about earlier. I thought that lime curd would be a nice contrast to the coconut and white chocolate, so I made that to go between the layers.
I wanted to do a Swiss meringue buttercream for the frosting because I prefer the taste of that to an American buttercream, which I usually find too sweet. So, I did a white chocolate version to which I added some coconut cream, coconut extract and some lime zest to bring the whole cake together.
The recipe idea from The Great British Bake-Off that I based my cake on covered the sides of the cake in a white chocolate collar. I’d never done this before, so I decided to try that as well. Generally, that went okay, but I must not have chilled the coloured chocolate enough before spreading the plain white chocolate over top because I ended up with more of a graffiti look than the swirls I was going for. I still thought it looked rather pretty! I topped the cake with some more shredded coconut and a bit of lime zest for colour and my cake was complete!
The Taste Test
Well… since I gave my cake away, I didn’t get to try the cake all put together! But I did try the components and each was very good. The friend who got the cake gave it rave reviews and sent me a few pictures. The pictures of the cake crumb looked nice and moist and the coconut flavour came through well. All-in-all, I would say the cake was a success!
Coconut White Chocolate Cake with Lime Curd
This celebratory cake has layers of coconut and white chocolate cake, filled with a tart lime curd and surrounded by a delicious coconut and white chocolate swiss meringue buttercream. To take the cake to the next level, you can also make a white chocolate collar to surround the sides of the cake. Cake adapted from Cook’s Illustrated.Ingredients
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For the Cake
- For the Lime Curd
- For the Coconut and White Chocolate Swiss Meringue Buttercream
- For the white chocolate collar
Instructions
- Adjust your oven rack to the lower-middle position and heat the oven to 325 F/160 C. Grease and line 3 8-inch round cake tins, grease and flour the parchment paper and sides of the tin.
- Whisk egg and egg whites together in a medium bowl. Add coconut cream, water, vanilla and coconut extract and whisk until thoroughly combined.
- In a large bowl, mix together flour, sugar, baking powder and salt.
- Add butter, one piece at a time and mix on low speed until only pea-sized pieces remain.
- Add half of the egg mixture and mix on medium-high speed until light and fluffy, about 1 minute.
- Add remaining egg mixture and mix on low speed until incorporated about 30 seconds.
- Gently fold in coconut and white chocolate chips until the mixture is combined.
- Divide batter evenly between the prepared pans and bake until a toothpick inserted in the centre comes out clean, about 20-25 minutes. Let the cakes cool in the pans for 10 minutes. Remove cakes from pans, discard parchment and let cool completely on racks, about 2 hours. For the Lime curd
- Whisk together egg yolks, sugar, lime zest, lime juice and salt in a large metal bowl or the top pot of a double boiler.
- Place over a pot filled with one inch of barely simmering water. Cook over medium heat, whisking constantly until thick and similar in texture to a Hollandaise sauce, about 5-10 minutes.
- Remove from heat and whisk in butter.
- Pour curd into a small bowl and place plastic wrap directly on the surface of the curd to prevent it from forming a skin.
- Chill in fridge until completely cool. For the Buttercream
- Place egg whites and sugar into the bowl of a stand mixer, whisk until combined.
- Place the bowl over a double boiler on the stove and whisk constantly until the mixture is hot and no longer grainy to the touch (approx. 3mins). Or registers 160F on a candy thermometer.
- Place the bowl on your stand mixer and whisk on med-high until the meringue is stiff and cooled (the bowl is no longer warm to the touch and the temperature of the meringue is 69-72 F/21-22 ). This could take up to 15 minutes. If the mixture is still not cool enough after 15 minutes, chill in the fridge for 5-10 minutes until it is cool enough. It is important that the mixture is not hot, or you will end up with soupy or too soft buttercream.
- Slowly add the cubed butter, one piece at a time, and mix until smooth.
- Pour in the melted white chocolate, coconut cream, vanilla extract, coconut extract and lime zest and whip to combine, about 1 minute. The buttercream may be kept covered at room temperature for up to 12 hours. For Assembly
- Place a dollop of the buttercream in the middle of your cake board and place one cake layer on top. Press lightly to secure.
- Spread a thin layer of buttercream over the top of the cake and build up a higher ring around the edges. Spread 1/2-3/4 cup of lime curd in the centre of the buttercream ring. Top with the second layer of cake.
- Repeat the buttercream and lime curd layer and top with the final layer of cake, this time putting the cake layer upside down so that the top is nice and flat. Chill the cake for 15 minutes in the freezer or 30 minutes in the fridge to set the buttercream.
- Once the cake has been chilled, spread a thin layer of buttercream over the tops and sides of the cake. Chill once more to set the buttercream.
- Add a final layer of buttercream over the tops and sides of the cake and use either an offset spatula or bench scraper to smooth the frosting. Add more frosting to any wholes in your buttercream and repeat the smoothing process until you are happy with the look of the cake. At this point, the cake can be topped with extra grated coconut and lime zest and be finished, or you can proceed to the next step and make a chocolate collar. Keep the cake chilled in the fridge while you make the collar or until serving. Remove the cake from the fridge 30 minutes before serving. For the White Chocolate Collar
- Melt the white chocolate in a bowl set over a pan of gently simmering water and stir until smooth. Remove the bowl from the heat and leave the chocolate to cool slightly. Lay the acetate strip on the work surface on top of a sheet of parchment paper.
- Spoon 1½ tablespoons of melted chocolate into a small bowl, add a tiny amount of yellow food-colouring paste and mix until the chocolate is bright yellow. Spoon 1½ tablespoons of melted chocolate into another small bowl, add a tiny amount of green food-colouring paste and mix until the chocolate is bright green. Pour each coloured chocolate into a piping bag fitted with a fine writing nozzle and pipe swirls of each all over the acetate strip. Chill for 10–15 minutes, until set firm.
- Using an offset spatula, spread the remaining melted white chocolate over the chilled swirls in an even layer. Leave at room temperature until cold and the chocolate has nearly set.
- Carefully wrap the chocolate collar around the outside, leaving the acetate in place. Place the cake in the fridge for about 10 minutes, until the collar has set firm, then carefully peel away the acetate.