Love and Olive Oil

Rainbow Cake

I think you all know what this time of year is. Yes, I know it’s Thanksgiving, but more importantly, it’s also Robin’s birthday. My little sister. Who loves cake. And every year she chooses to visit us for her birthday. She could spend her precious Thanksgiving break anywhere, and yet for the past 3 years, without hesitation, she’s come to Nashville. Honestly, I think it’s because of the cake.

Last year’s cake was pretty darn delicious (and pretty tall too) in all its chocolatey goodness. But I really think I’ve outdone myself this year.

What, you say? That cake doesn’t look like anything special… it looks like just a plain old white cake with a shaky piped greeting…

Well, I say to you, let me cut you a piece…

Bam! Didn’t see that one coming, did you?

Indeed, I tackled in the infamous Rainbow Cake, as seen on Martha Stewart and I’m sure countless other blogs. So no, it’s not original. But that doesn’t make it any less fabulous.

I’ll admit, it wasn’t easy, and I joked that this cake was doomed from the start. From an overly-bubbly and oddly textured cake, to cake layers flying through the air and landing on the floor (thanks, cats!), which lead to a necessary rebaking of the green and yellow, to fingertips meeting with sharp knives, to an entirely too-large batch of buttercream that kept my mixer huffing and puffing for nearly 75 minutes… no, it wasn’t easy at all. But the reaction, the surprise when you make that first cut, that alone made it entirely worthwhile. Robin has officially declared this her Favorite. Birthday. Cake. Ever. Success!

I better start planning now, because I really have no idea how I’m going to top this one next year…

Rainbow Cake with White Chocolate Buttercream

This recipe is a bit uneven. I used 6″ pans, and the layers were too thick and and I had way too much frosting. I think it’d be better suited to a 7″ or even 8″ cake, so adjust as necessary depending on the size of your cake pans.

Cake recipe from Cooks Illustrated. Frosting recipe from Martha Stewart.


For Cake:
2 1/4 cups cake flour (9 ounces)
1 cup whole milk, at room temperature
6 large egg whites (3/4 cup), at room temperature
2 teaspoons almond extract
1 teaspoon vanilla extract
1 3/4 cups granulated sugar (12 1/4 ounces)
4 teaspoons baking powder
1 teaspoon table salt
12 tablespoons unsalted butter (1 1/2 sticks), softened but still cool
Red, orange, yellow, green, blue, and purple gel food coloring

For Frosting/Filling:
2 1/2 cups granulated sugar
10 large egg whites
2 pounds (8 sticks) unsalted butter, cut into tablespoons, softened
2 teaspoons pure vanilla extract
1 pound best-quality white chocolate, melted and cooled


Preheat oven to 350 degrees. Prepare your cake pans by first liberally buttering the pans, then line the bottoms with parchment paper rounds. Butter the rounds and set aside.

Pour milk, egg whites, and extracts into 2-cup glass measure, and mix with fork until blended. Mix cake flour, sugar, baking powder, and salt in bowl of electric mixer at slow speed. Add butter; continue beating at slow speed until mixture resembles moist crumbs, with no powdery streaks remaining. Add all but 1/2 cup of milk mixture to crumbs and beat at medium speed (or high speed if using handheld mixer) for 1 1/2 minutes. Add remaining 1/2 cup of milk mixture and beat 30 seconds more. Stop mixer and scrape sides of bowl. Return mixer to medium (or high) speed and beat 20 seconds longer.

Divide batter evenly between six medium bowls. Add enough of each color of food coloring to each bowl, whisking, until desired shade is reached. Transfer each color to an individual cake pan. Transfer to oven and bake until a cake tester inserted into the center of each cake comes out clean, about 15-25 minutes (working in batches if necessary).

Let cakes rest in pans for 3 minutes. Loosen from sides of pans with a knife, if necessary, and invert onto wire rack. Allow to cool completely. At this point, the layers can also be wrapped in plastic wrap and frozen.

To make frosting, put sugar and egg whites in the heatproof bowl of an electric mixer, and set over a pan of simmering water. Whisk constantly until sugar is dissolved and mixture registers 140 degrees on an instant-read thermometer.

Transfer bowl to an electric mixer fitted with the whisk attachment; beat on medium-high speed until fluffy and cooled, about 10 minutes. Continue beating until stiff peaks form.

Reduce speed to medium-low; add butter by the tablespoon, beating well after each addition. Beat in vanilla and white chocolate. (Any leftover frosting can be refrigerated in an airtight container up to 3 days or frozen up to 1 month.)

To assemble, using a serrated knife, trim tops of cakes to make level. Place four strips of parchment or waxed paper around perimeter of a cake stand or lazy Susan. Place the purple layer on the cake plate. Scoop a 1/2 cup (or more for a larger cake) buttercream filling over the first layer and spread with a small offset spatula so it extends just beyond edges. Repeat process with blue, green, yellow, and orange layers.

Place the remaining red layer on top, bottom-side up. Gently sweep away any loose crumbs with a pastry brush. Using an offset spatula, cover the top and sides with a thin layer of frosting (also use any of the excess frosting visible between the layers). Refrigerate until set, about 30 minutes.

Using a large offset spatula, cover cake again with remaining frosting.

All images and text © / Love & Olive Oil

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  1. Totally amazing! I just showed this beautiful cake to my husband, my birthday’s coming up ya know! I’d better get the ingredients together, (and make it myself) ;)!
    voted by the way, hope you win!

  2. that cake looks awesome! may i ask what gel food coloring you used? i am from germany and we don’t have those really vivid food coloring here but a friend of mine is in the usa right now and she would bring me some when i tell her which ones. ^^

  3. There is some major good awesomesauce in here! Kudos on the fine work :) Nomnomnomnomnom…

  4. It may not be original, but it’s the first time I’VE seen it! And it’s breathtaking. Happy Birthday to Robin, and so happy she enjoyed the cake!!!! And cheers to the big sister, too, for making it so special.


  5. Love it and you got my vote!

  6. I discovered this cake on whisk-kid’s blog. She was the one on Martha Stewart baking this cake. She always has wonderful recipes (: You do too, I think you did a beautiful job with this cake!

  7. It is beautiful! I hope you win! Good luck! :) #butterlove

  8. i love, love, love this cake! it’s almost too much fun. i’ve made a variation on the rainbow cake, and i did all my layers in very light pastel colors. it was gorgeous, but indeed this cake is a labor of love!

  9. The cake is very amazing! Just like the dream come to reality.

    A great job!

  10. It’s fabulous indeed! I still haven’t found the courage to attempt it myself so great job!

  11. I love how your cake came out, I will definitely give it a try. Maybe red and green for xmas? Either way itll be delish!

  12. absolutely breathtaking!!!!! first time i dropped by your site and this is what i’m greeted with. i’ll be hungry for more!!!! such inspiration! cheers!

  13. WOW, that is a cake that would make Bettie Landis proud!!! Great job Lindsay.

  14. Wonderfull, colourful cake! Thank you :)

    yemek tarifleri

  15. Wow! That is one impressive cake. And you have much more patience than I do. :)

  16. what a gorgeous cake! and yes it is hard work isnt it but SO SO worth cutting into it and seeing all the bright colours shining out :D

  17. Wow! Just stumbled upon your blog, and what an incredible, technicolour introduction. Not only do I Want. That. Cake. Now. I also want to read more of your recipes. Hurrah!

  18. This is one of the best looking cakes I’ve ever seen! Beautiful job, especially after all that you endured!

  19. Alright, the rainbow is beautiful, but the fact that it uses ALMOST TWO AND A HALF POUNDS OF BUTTER is even more beautiful.

  20. Gorgeous! Great job! Gonna have to give this one a whirl some time. I’ve done rainbow cupcakes but this beats those hands down!

  21. My gosh that is too good to be true. I’d love that for my birthday. Looks delicious too!

  22. Wow that is one epic cake! It’s just magnificent :)

  23. consider me impressed :)

  24. This is beautiful! I can only imagine how much patience was required. I don’t have the patience to make a regular, normal, one-layered cake without frosting – so I am very impressed. And it looks like it produces monster slices.

  25. AAAAA-mazing! This cake is so beautiful and you did such a great job with it! I just love it!

  26. how amazing is this cake?! LOVE it!

  27. As a mom with TWO December birthdays to plan, I luv this cake! It is such a challenge to make the day special in the midst of all the holiday goodies! This cake is a winner! I know my family would love it!

  28. Your Sis is awful lucky! Pretty cake.

  29. This is SO pretty! I love that it looks like a simple white cake… And it’s not at all! :)

  30. So pretty! You’re right though – the green and yellow layers do look a little more evenly textured than the others. How weird! I’m glad it was still a hit though!

  31. I think baker’s are artists. I love beautiful photos of cakes and your’s is absolutely splendid. Happy Birthday to your sister. Yummy & Beautiful.

  32. That is so beautiful Lindsay. I really love the second picture- all the lovely bright colors against the black backdrop…my daughter would absolutely love this for her birthday next month!

  33. This looks so yummy!!!!!!!!!!!!

  34. Oh my gosh! This is amazing! I’ve never seen it before, so I wasn’t expecting all that colour. What a lucky sister you have! x

  35. wow that turned out beautifully!

    I’m going to go vote for you right meow!

  36. GORGEOUS!!!!!! (And I love the photography too!)

    I’ve wanted to try one of those for awhile. Bravo for making it happen — it looks absolutely perfect! And completely delicious. :-) Hope you enjoyed it!

  37. Wow you totally rocked the rainbow cake. Just gorgeous!

  38. Wow, what a colourful cake!
    :-) Mandy

  39. This is a truly awesome cake! I need to get better at frosting…

  40. Gorgeous!

    I voted for you too! Good luck!

  41. You say there was way too much frosting…

    Was there too much frosting for the cake? Or was it just too much volume for your mixer to handle? If it was more than needed for the cake, then how much would you cut the frosting recipe?


    • Both. The meringue took 30-40 minutes to cool to room temperature, vs. like 10 minutes with smaller, cupcake-size batches. But it ended up being way too much frosting for the cake anyway, I’ve got about 4 cups left that I froze. Maybe more appropriate for an 8 inch cake, not 6?

  42. You get my vote, not just because I feel sorry for you with all the disasters and the 75 minutes you had to listen to your stand mixer run! :)

    It’s gorgeous! What kid wouldn’t love this?

  43. Beautiful job!! I’ve been wanting to make it since seeing it done on the Martha Stewart show.

  44. what a fun cake! i love the vibrant colors!:)

  45. It may have been a pain to make, but WOW. The cake is gorgeous! You did a fantastic job. I don’t envy you having to top that next year!

  46. Happy Birthday to your Sister! I know she loved her cake- so beautiful and very impressive!

  47. Stunning vivid colors in your cake! What a nice sister you are!!! Beautiful cake – love the decorating you did.

  48. Beautiful job!!

  49. That is BEAUTIFUL! Your sister is so lucky!

  50. is there anyway to make this using less layers? I would like to make this using christmas colors and only maybe 3 or four layers.

    • Definitely! I think this cake could be adapted in a myriad of ways. :) The recipe would scale well for maybe four 8-inch layers, I think!

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