Happy St. Patrick’s Day! We’ve done the green foods thing. We’ve done the other green foods thing. We don’t mess with corned beef, potatoes, or cabbage of any sort around here, so the only thing left to do to get us in the St. Paddy’s Day spirit must be a rainbow dessert!

Okay, fine, if I must. Twist my arm already. It’s not like I’m obsessed with rainbow desserts or anything….oh wait.

Rainbow in the Clouds Cake - with rainbow buttercream and fluffy cloud frosting | From SugarHero.com

This time around, I’m leaving the cake alone—no more bazillion layers of multi-colored cake for me. Instead, this is a “Rainbow in the Clouds” cake, with swirls of cloud-like vanilla meringue frosting, layers of fluffy yellow cake, and a surprise rainbow of gorgeous multi-colored buttercream frosting hiding between each cake layer.

Rainbow in the Clouds Cake - with rainbow buttercream and fluffy cloud frosting | From SugarHero.com

The rainbow frosting effect is ridiculously easy! Well, ridiculously easy after you’ve gone to the trouble of dividing the frosting into 6 different bowls, coloring them separately, and putting them into 6 different piping bags. Annoying.  But all that fiddly work is worth it, once you pipe those bright rings of buttercream and see your rainbow start to take shape. I loved this cake even before I cut into it—how could anyone not love that cheery rainbow bulls-eye?

Rainbow in the Clouds Cake - with rainbow buttercream and fluffy cloud frosting | From SugarHero.com

It wasn’t enough to have a super stealthy rainbow hidden in the clouds—I wanted a big honkin’ in-your-face rainbow, too. So I made one out of fondant and set it on top of the cake for the perfect topper. The decoration has to  be made several days in advance, so it has time to dry and harden and be stable enough to stand up on its own.

Rainbow in the Clouds Cake - with rainbow buttercream and fluffy cloud frosting | From SugarHero.com

Wondering how to make a fondant rainbow of your own? Of course you are. I’ve got your back! For this rainbow, and for almost all of my fondant work, I’m using homemade marshmallow fondant. I sometimes buy red or black fondant, because those colors can be hard to make at home, but for almost everything else, I keep a stash of the DIY stuff handy. It’s a dream to work with, and the flavor is better than many store brands.

How to Make A Fondant Rainbow | From SugarHero.com

And those coins at the bottom of the cake? Chocolate coins, of course! The gold foil-wrapped ones that you buy would be perfect for this. I didn’t have any of those around except for a few very old Hanukkah coins that are probably no longer edible. (Note to self: clean out candy cupboard.) I did have a chocolate coin candy mold from another project, so I made my own chocolate coins (using this mold) and sprayed them with gold Wilton Color Mist. The coins are optional, but I do think they give the cake a bit of that leprechaun je ne sais quoi.

Rainbow in the Clouds Cake - with rainbow buttercream and fluffy cloud frosting | From SugarHero.com

Can we talk about eggs? Let’s talk about eggs. You will need a lot of them….like, over a dozen. When you’re making a meringue-based buttercream AND a separate meringue frosting, you’re going to have to crack a few eggs! (Ba-dum-ching.) I tried to balance things out by using a yellow cake recipe that only uses yolks, so it doesn’t feel as wasteful. And you will be able to feed a LOT of people with this mega cake, so all of those eggs are going to a good cause.

But because I know that some people don’t like recipes that require so many egg whites, I will say that you can use any buttercream recipe in the center, so feel free to swap my Swiss meringue one with a traditional American buttercream instead. You could even use a different cake recipe if you’d like. The meringue’s not negotiable, though—the fluffy cloud frosting must stay. This is me putting my foot down.

Rainbow in the Clouds Cake - with rainbow buttercream and fluffy cloud frosting | From SugarHero.com

And after all that, how does it taste? Like the best dang homemade cake you’ve ever had! How could it not, with all of those layers of cake and frosting? I chose to keep things simple and used lemon flavoring in the cake and buttercream, but you could use plain vanilla, or almond, or coconut, or orange, or even mix and match… you get the idea. It’s not about the recipes so much as the technique and presentation, so I hope you take this idea and run with it. And please, show me what you make if you give it a try!

Rainbow in the Clouds Cake - with rainbow buttercream and fluffy cloud frosting | From SugarHero.com

 


Rainbow in the Clouds Cake
 
I chose to flavor my cake and buttercream with lemon, but you can use any extract you like: vanilla, coconut, almond, and orange would also all be delicious.
Author:
Serves: 12-16
Ingredients
For the Cake:
  • 21 oz (3 cups) granulated sugar
  • 21 oz (6 cups) sifted cake flour (measured after sifting)
  • 2 tbsp + 2 tsp baking powder
  • 1½ tsp salt
  • 12 egg yolks
  • 2 cups milk, at room temperature
  • 1 tbsp lemon extract (or other flavoring of choice)
  • 12 oz unsalted butter, at room temperature
For the Rainbow Buttercream:
  • 9 egg whites
  • 14 oz (2 cups) granulated sugar
  • 1 lb unsalted butter, soft but still cool
  • 1 tbsp lemon extract
  • ¼ tsp salt
  • Gel food coloring in red, orange, yellow, green, blue, and purple (I like Americolor brand)
For the Fluffy Cloud Frosting:
  • 6 egg whites
  • 9.3 oz (1.3 cups) granulated sugar
  • 2 tsp vanilla extract
  • Pinch salt
Optional Decorations:
  • Fondant Rainbow
  • Gold Chocolate Coins
Instructions
To Make the Cake:
  1. Preheat the oven to 350 F. Line four 9-inch cake pans with parchment rounds, and spray the parchment and pan sides with nonstick cooking spray. (If you have 9x3-inch cake pans, you can use two of those instead.)
  2. Combine the sugar, cake flour, baking powder, and salt in the bowl of the stand mixer fitted with a paddle attachment. Mix on low speed for about a minute to combine the dry ingredients.
  3. Lightly whisk together the egg yolks and about a quarter of the milk (it doesn’t have to be a precise measurement) and the lemon extract, and set aside for now.
  4. Add the remaining milk and the softened butter to the large mixing bowl and mix on low speed until the dry ingredients are moistened. Turn the mixer to medium speed and mix for a minute and a half.
  5. Add the egg yolk mixture in three batches, mixing for 20-30 seconds after each addition, until you have a smooth batter. Scrape the bottom and sides of the bowl with a rubber spatula, and give the batter a few more stirs to make sure everything is incorporated. Divide the batter between the four pans—if you have a kitchen scale, each pan should get about 20 oz of batter. Bake them at 350 F for 30-35 minutes, until the sides just start pulling away from the pan, and a toothpick inserted into the center comes out clean.
  6. Let the cakes cool on a wire rack for 10 minutes, then gently turn them out and let them cool completely. I find it’s easiest to assemble cakes that have been chilled, so if you have time, wrap them with plastic wrap and put them in the freezer for at least 30 minutes, until they are firm but not frozen all the way through. If you are making these in advance, they can stay in the freezer for up to several weeks. Let them partially defrost, until they are firm but not rock-hard, before assembling.
To Make the Rainbow Buttercream:
  1. Combine the egg whites and the granulated sugar in the bowl of a large stand mixer, and whisk them together. Choose a small saucepan that lets you fit the base of the stand mixer snugly into the top of the saucepan—this is your makeshift hot water bath. (Alternately, you can use a different bowl or an actual bain marie and then transfer the mixture to a mixing bowl once it’s heated.) Add an inch of water to the bottom of the saucepan, and bring the water to a simmer.
  2. Place the mixing bowl on top of the saucepan, making sure that the bottom isn’t in contact with the water, and heat the egg white mixture. Whisk frequently so that the egg whites don’t cook. Continue to heat the whites until they are hot to the touch, and when you rub a bit between your fingers, you don’t feel any grittiness from the sugar. Once the whites are hot, transfer the mixing bowl to your mixer and fit it with a whisk attachment.
  3. Beat the whites on medium-high speed until they are a shiny, stiff, voluminous meringue, and are no longer warm to the touch—feel the outside of the bowl, and make sure that it is around room temperature. Depending on your mixer and the temperature of your environment, this may take 15-20 minutes, or more. Reduce the speed to medium-low and add the softened but cool butter in small chunks, a tablespoon at a time, making sure to wait in between additions. It may separate or look a little gloopy at this point—fear not. Once all of the butter is added, increase the speed again and whip until it comes together and is light and fluffy. If, after 5 minutes, it hasn’t come together, refrigerate the mixing bowl for 5-7 minutes, to cool the mixture down, and whip it again until it has thickened and is smooth and silky. Add the vanilla extract and salt.
  4. The buttercream can be made in advance and kept at room temperature if you’re going to use it the same day, or refrigerated. If it has been chilled, let it sit at room temperature until completely soft, then re-whip it to get the smooth texture back before you use it.
  5. When you're ready to use it, divide it between 6 bowls. You'll need to estimate the portions, but you'll want to have 3 of the frosting portions smaller (for the colors that are in the center of the cake) and 3 of them larger (for the colors that go around the outside.) In my case, I mixed smaller amounts of purple, blue, and green, and larger amounts of yellow, orange, and red. If you're not worried about every rainbow frosting layer having the colors in the same order, you can make the frosting portions approximately the same size and just pipe the colors in a different order for each layer, so you'll use about the same amount of every color of frosting.
  6. Color each bowl with a different gel food coloring, adding enough so that you get a strong, vibrant color. Transfer each color to a pastry bag fitted with a large round tip.
To Assemble and Make the Fluffy Cloud Frosting:
  1. First, assemble the cake so it can be chilling while you make the fluffy cloud meringue. Trim the tops of the cakes so that they're level. Place one cake round on a cardboard cake circle, and pipe a circle of purple frosting in the center of the cake. Pipe a thick blue ring around it, then add a green ring around that. Continue to pipe circles of buttercream, adding yellow, orange, and red colors, until you reach the edge of the cake.
  2. Add a second cake round on top, and repeat the frosting circles. Add a third cake round and use the rest of your frosting to make the final rainbow frosting layer. Place the last cake round on top, press down gently, and make sure the sides of the cake are straight. Refrigerate the cake while you prepare the meringue topping.
  3. Combine the egg whites and the granulated sugar in the bowl of a large stand mixer, and whisk them together. Choose a small saucepan that lets you fit the base of the stand mixer snugly into the top of the saucepan—this is your makeshift hot water bath. (Alternately, you can use a different bowl or an actual bain marie and then transfer the mixture to a mixing bowl once it’s heated.) Add an inch of water to the bottom of the saucepan, and bring the water to a simmer.
  4. Place the mixing bowl on top of the saucepan, making sure that the bottom isn’t in contact with the water, and heat the egg white mixture. Whisk frequently so that the egg whites don’t cook. Continue to heat the whites until they are hot to the touch, and when you rub a bit between your fingers, you don’t feel any grittiness from the sugar. Once the whites are hot, transfer the mixing bowl to your mixer and fit it with a whisk attachment.
  5. Beat the whites on medium-high speed until they are a shiny, stiff, voluminous meringue, and are no longer warm to the touch—feel the outside of the bowl, and make sure that it is around room temperature. Add the vanilla extract and salt and mix them in.
  6. Pile a big cloud of meringue on top of the cake, and gently cover the tops and sides with the fluffy meringue. Use a spoon or spatula to create big swoops and swirls in the meringue.
  7. Place the fondant rainbow on top of the cake, and stick two wooden skewers behind it to prop it up vertically. Scatter the gold chocolate coins around the bottom of the cake. For the best taste and texture, this cake is best enjoyed at room temperature the same day it is made, but it can be kept for several days in the refrigerator. (The meringue on the outside will get chewier as the days go on.) The assembled cake can also be made several days in advance and kept, wrapped in plastic wrap in the refrigerator, until you're ready to add the meringue and serve it.

Fondant Rainbow
 
Author:
Ingredients
  • 10 oz white fondant (I like using homemade marshmallow fondant)
  • Gel food coloring in red, orange, yellow, green, blue, and purple (I like Americolor brand)
  • Powdered sugar
  • Corn syrup
Instructions
  1. Dust your work surface with powdered sugar. If you have plastic food-safe gloves, now is a good time to wear them, so that your hands won't get food coloring on them.
  2. Divide the fondant into 6 pieces. Press one piece into a disc, and put a few drops of yellow gel food coloring in the center. Fold the sides over the coloring, so you have a fondant ball, and knead it between your hands. Soon you'll start seeing streaks of color come through the fondant. Continue to knead until the fondant is a uniform color. Add more food coloring if necessary, until you get a bright yellow. If at any time the fondant gets too sticky, dust your hands with powdered sugar. Repeat with the rest of the fondant balls until you have 6 rainbow colors.
  3. Roll out the purple fondant until it is a long strip a little thicker than ¼-inch. Cut it into a ½-inch long strip. Place a round cookie cutter or glass a baking sheet covered with waxed paper and dusted with powdered sugar. Wrap the purple fondant around the cutter, using it as a guide to make the center of the rainbow round.
  4. Repeat the process with the blue fondant, cutting out a ½-inch strip. Paint the side of the purple strip with a little corn syrup, and press the blue fondant into it to make them stick together. Continue to assemble the rainbow this way, sticking each color together with a thin layer of corn syrup.
  5. When you finish the rainbow, remove the cutter and trim the bottom so that it's a clean, straight line. Let the fondant rainbow sit for at least 2-3 days, until it is sturdy and firm. Flip it after the first day so that the bottom has a chance to dry out too. The fondant rainbow can be made weeks or even months in advance.

 

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