Wednesday, July 31, 2013

Watermelon Sponge Cake



About a month ago, I got a special request from Jeremy's mom to come up with a recipe for a watermelon cake so she could make it for his younger brother's birthday (he is a watermelon enthusiast). It was a tricky challenge, since watermelon doesn't really taste like watermelon anymore once you heat it up, and most cakes  involve baking. So, after much thought and one failed cake-making attempt, I decided to leave the watermelon out of the actual sponge cake itself, and instead focused on creating the watermelon flavors within the layers. I ended up making a cold-pressed watermelon simple syrup and then beating it into some heavy cream for a watermelon whipped cream. Then I mixed more of the syrup into a chilled curd to make a fresh and tasty watermelon curd. I prepared the sponge cake using a simple recipe I came across here, and spread the watermelon whipped cream and curd between each layer when assembling.


The end result of all this brainstorming and planning and tomfoolery was the single most refreshing and summery cake I've ever had. Bright, fresh, and cool; the light and airy spongecake was the perfect match for the rich fruity fillings. It sliced incredibly easy, and was altogether pretty easy to make. The most complex part was folding the egg whites into the batter, if you've never attempted this before I  highly recommend taking a gander at this tutorial. Very helpful! The general purpose of folding in the egg whites in rather than stirring them is to keep all those nice tiny bubbles you whipped up intact, so that way when the cake bakes it retains that light and airy texture, rather than the more dense texture of traditional yellow cakes. The fluffiness of the cake is perfect for the heat of late, I hope it finds its way into your kitchen this summer, it is a real treat!



Sponge Cake

6 eggs, separated
1 cup sugar
1/4 cup water
1 cup flour
1/2 teaspoon cream of tartar
1/4 teaspoon salt

Cold Press Watermelon Simple Syrup

1/2 cup watermelon puree
1 cup granulated sugar

Watermelon Curd

1/2 cup plus 2 tablespoons sugar
5 tablespoons butter
2 eggs
1 egg yolk
3 tablespoons watermelon syrup
4 drops pink food coloring (optional)

Watermelon Whipped Cream

2 cups heavy whipping cream
2 tablespoons watermelon syrup


First, make the watermelon syrup. Mix together the watermelon puree and sugar in a medium sized bowl. Cover and refrigerate for 4 hours or overnight. Strain the syrup though a mesh sieve to remove any large particles and seeds. Reserve the syrup in a separate bowl and cover and refrigerate it until use. (You will have some left over after the recipe, I recommend using it as a mixer for cocktails or stirring it into some fresh lemon juice for a watermelon lemonade).

To make the watermelon curd, cream together the butter and sugar until smooth. Add the eggs, one at a time, and then the yolk, and mix until blended. Pour the mixture into a small thick-bottomed saucepan and cook over low heat whisking constantly, until the temperature of the mixture reaches about 170 degrees Fahrenheit with a candy thermometer, or until the mixture has thickened significantly (it usually takes between 8 and 15 minutes depending on your heat level and stovetop). Remove from heat immediately and continue whisking for the first few minutes so the mixture doesn't cook onto the bottom of the hot pan. Allow to cool to room temperature, then whisk in 3 tablespoons of the chilled watermelon syrup and the optional pink food coloring until incorporated. Cover and place the curd in the refrigerator until use.


To make the cake, Preheat the oven to 325 degrees Fahrenheit. Line the bottom of (3) 8-inch cake pans with parchment paper. Set aside. In a large bowl, beat the egg yolks at medium-high speed until thick, about 2 minutes. Add the sugar 1/4 cup at a time, then add the water and mix until blended. Lastly, add the flour and mix until it is just incorporated.


In a separate bowl, beat the egg whites with a whisk attachment at high speed until foamy, then add the cream of tartar and salt and continue beating until stiff peaks form, but do not over beat. Fold the egg white mixture into the bater until incorporated, then evenly distribute the batter between the three cake pans. Place in the oven and bake for 30-40 minutes or until the cakes turn golden brown on top. Turn the oven off and open the oven door halfway. Allow the cakes to cool in the oven for 30 minutes before running a knife around the edge of each pan to loosen the cakes grip. Flip the pans over onto a wire rack and remove the pan. Allow the cakes to cool completely, then trim the crust.


While the cakes are baking and cooling, you can prepare the whipping cream. Beat the heavy cream and 2 tablespoons of the watermelon syrup with a whisk at high speed until thick and fluffy, but take care not to over beat. Cover and refrigerate until use.

To assemble, place a layer of the cake on the serving surface. Spread a smooth layer of whipped cream on top of the cake, and then spread a layer of the curd on top of the whipped cream. Repeat until all of the toppings and cake layers are used. Serve immediately and refrigerate and leftovers.




45 comments:

  1. I've never seen watermelon in a cake before, but it sounds (and looks) wonderful, especially the watermelon curd part, that the idea of the week :)

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  2. Your watermelon cake is so pretty. I know, it's quite tricky to bake watermelon into the cake itself, plus, it's so watery. :) You are genius to make the curd and watermelon syrup and mix into the buttercream. Your cake is looking gorgeous with all those layer of colors too.

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    1. Thanks Amy! Yes the first cake came out okay but not great, the second attempt was sooooo delicious though. So glad I didn't get discouraged and give up :)

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  3. I love the way you think --- and I'm never disappointed when I visit your page. I just made a Watermelon Gin Rickey that might go well with this beautiful cake.

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    1. Thank you Sue! I am so glad you find yourself contented when you visit here :)

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  4. Ditto my last comment about your photos - but I have to add that this gorgeous cake has to be made soon! Love it!

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    1. Thank you so much Kristen! I highly recommend it! :)

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  5. Eva, what a beautiful cake! I have to admit, the idea of watermelon and cream sounds completely incompatible to me, but your execution looks pretty much perfect. Also, sponge cakes are the best thing ever in the summer, so I am sold. Jeremy's brother will love it. :)

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  6. Haha, thank you Linda! We are agreed, sponge cakes are definitely the best thing ever in the summertime. So light and airy!

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  7. Gosh this cake is simply gorgeous!!! I mean wow, seriously amazing! Watermelon in a cake? That is so genius!

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  8. Creativity to the max! If someone asked me to put watermelon in a cake, I would probably just carve a cake(ish) shape out of a piece of watermelon! But this totally makes sense. Genius.

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  9. You are a better person than me times a million for this. If someone had requested a watermelon cake, I just would have been like "Nah. Can't do it. Watermelon's a no bake, dude." But you're so creative! I love those visible layers and a watermelon curd sounds so refreshing. Amazing, Eva.

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  10. It looks absolutely lovely!! You did an awesome job!!

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  11. Watermelon is not something I would normally think of when it comes to cake, but what a perfect summertime treat.

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  12. What a lovely summer cake idea!

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  13. Wow... I am speechless! Why? I am a watermelon FANATIC. My kitchen is pretty much all watermelon from pink or red accessories to watermelon gadgets, bowls, decor, sugar and flour containers, etc. I cannot wait to get in the kitchen and try to recreate your masterpiece! Wow! THANK YOU!

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    1. One other thing I forgot to add... a use for the extra syrup: Three Olives Watermelon vodka, watermelon syrup, mixed with pear soda and served with frozen watermelon cubes instead of ice. YUMMY!

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  14. Cold press syrup, FTW!!! Hells yes. :D So perfect for watermelon too, since those things are pretty much dying to turn into juice as it is.

    This really does sound like the most refreshing cake ever. I've always been a huge fan of sponge cake + berries + cream in the warmer months, but swapping the berries for watermelon...it doesn't get any more summery than that! And it's so beautiful too, especially with the rind bits decorating the top! :)

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    1. Thanks Carey! It was so nice and cool and refreshing. I really liked the texture of the sponge cake too, perfect for whipped cream and fruit like you said ;)

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  15. this looks decadently delicious! heavenly!
    xx

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  16. This recipe blows my mind. Who would have thought of watermelon in cake?! And a super refreshing, summery cake at that? Wow. I hope your almost-brother-in-law enjoyed it! I made a pie for Kevin's very discerning father when they came to visit a few weeks ago, and he told me it was the best pie he's ever had. Baking for the in-laws can be high pressure, but so worth it when they like the result!

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    1. Awww that's awesome!! Baking something for someone you're trying to impress and having them love it is just the best. Especially when it's future in-laws :D

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  17. Eva the brainstorming and creativity you had to come up with this masterpiece is just astounding! I can imagine that baking with watermelon is a no-go. I've seen it grilled, but that's as 'hot' as I've ever seen it get. Great idea to focus on it between the layers. The spongey-ness of this cake is just beautiful as are the colors. Wow. So impressed! Pinned!

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    1. That is so kind of you to say, Averie. I am so glad you like the way I incorporated it into the cake. It's such a tricky fruit to capture the flavor of, but boy was it worth it! :)

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  18. Very unique combination and love your creativity. Perfect pictures to accompany your beautiful recipe. I'm sure your family enjoyed it.

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  19. Whoa this is stunning! So, so perfect for summer!

    Sues

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  20. this is definitely the first time i've seen watermelon in a cake, or even as a curd, for that matter. kudos on your cleverness, and your end result looks sensational!

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  21. OMG! I'm baffled! Speechless! How incredibly genius you are, Eva! Using watermelon in a sponge cake? - Outstanding idea! And adorable photos :)

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  22. I've never seen watermelon cake before. i'd like to try it!

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    1. Let me know how it turns out for you if you do :)

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  23. Your photographs are always so stunning. I love a good sponge cake, and oh my goodness does yours look perfect, I am so intrigued by the watermelon!

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  24. I love watermelon..I have never seen before the use of watermelon in a Cake, this looks delicious, I'll try to make it this different cake because I am a Cake Designer and work for Riya Cake Pune.

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    1. Oh awesome! Yes, definitely let me know how it turns out for you, I hope you like it!

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  25. This sounds amazing! I just discovered your blog via Pinterest (I love rose in deserts!)and I am so excited to check out all of your recipes.

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    1. Awww thank you so much Mary! I am so happy you found my blog and are having a good time looking around at all the recipes I've made over the years. If you try some of them let me know how they come out :)

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