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Flour Shop Rainbow Explosion Cake Kit

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We teamed up with Amirah Kassem's Soho-based Flour Shop bakery to bring you this exclusive kit for whipping up your own version of the Instagram-famous Rainbow Explosion Cake at home. Start by combining the premium cake mix and coloring gels to bake the six rainbow-hued layers, then use the cream cheese frosting mix and colorful candies to frost, fill and decorate your surprise-filled dessert.

Set includes:

  • 1 pouch Magical Vanilla Cake Mix
  • 6 Rainbow Coloring Gels
  • 1 pouch Magical Frosting Mix
  • 1 pouch Rainbow Explosion Mix (sprinkles)
  • 1 pouch Rainbow Polka Dots (sprinkles)
  • 4 lb. 5 oz. total.
  • Made in USA.
  • Cake Mix: Unbleached flour (wheat flour, malted barley flour, niacin, reduced iron, thiamin mononitrate, riboflavin, folic acid), sugar, non-aluminum baking powder (sodium acid pyrophosphate, bicarbonate soda, cornstarch, monocalcium phosphate), Bourbon vanilla powder, sea salt.
  • Frosting Mix: Powdered sugar, natural vanilla powder.
  • Sprinkles: Sugar, cornstarch, FD&C colors Red #40 Lake, Red #3, Yellow #5 Lake, Yellow #6 Lake, Blue #1 Lake, carnauba wax.
  • Liqua-Gel Color Pack: Water, high-fructose corn syrup, glycerin, sugar, Yellow #5, modified food starch, Red #3, Blue #1, Yellow #6, carrageenan gum, sodium benzoate (preservative), potassium sorbate (preservative), citric acid, xanthan gum, Red #40.
  • Rainbow Explosion Mix: Sugar, cornstarch, hydrogenated palm kernel oil, soy lecithin, gum arabic, confectioners' glaze, carnauba wax, reduced protein whey (milk), cocoa, corn syrup, tapioca dextrin, salt, Yellow #6, Yellow #5, Blue #1, Blue #2, Red #40, Red#3, titanium dioxide.
  • Rainbow Polka Dots: Sugar, cornstarch, Red #3, confectioners' glaze, carnauba wax, Yellow #5, Blue #1, Blue #2, Yellow #6, Red #40.
  • Contains wheat/gluten, tree nuts.
  • This product is prepared and packaged using machines that may come in contact with wheat/gluten, tree nuts, peanuts, soy.

Shipping Information

UPS can deliver most in-stock items within 3–5 business days. UPS is unable to deliver to P.O. boxes.

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Orders received by 9:00 p.m. ET Monday through Thursday will arrive the next business day; orders placed Friday through Sunday will arrive on the following Tuesday.

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If within 30 days, you are dissatisfied for any reason, you may return your purchase for a refund of the merchandise value. An original receipt or gift receipt is required for all returns and exchanges. Returns with a gift receipt will be refunded in the form of a Merchandise Credit for the amount indicated on the gift receipt. Returns with original receipt will be refunded in the original form of payment, cash and check refunds over $100 will be issued as a company check (may take 14 business days from time of request).

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  • Rated 5 out of 5 by from Great Birthday Surprise for Adults Too! I made the cake for my husband’s birthday. He and everyone loved the surprise cutting into the cake and seeing all the vibrant colors with sprinkles spilling out! The cake was moist and delicious. The vanilla white cake paired well with the cream cheese frosting and occasional crunch from the sprinkles. I started baking at 11am, and finished around 3:30/4pm. Put it in the fridge to set until I left for dinner until 5:30 and left it out until after dinner around 9pm. I had only 3-6in bake pans (from williams-Sonoma) and baked in 2 batches. Super fun to bake with the pretty colors. I had quite a bit of food coloring on my fingers and worried it may give my surprise away! I will definitely be purchasing again for the next Birthday, thanks!!
    Date published: 2019-12-13
    Rated 3 out of 5 by from Cute but didn't taste good I love the can, and the cake was beautiful. They were very generous with the sprinkles and the surprise worked really well. Unfortunately we all disliked the taste of the cake, and most of it got thrown away.
    Date published: 2019-11-11
    Rated 5 out of 5 by from Big Hit! Loved this kit. There were plenty of ingredients. There’s nothing worse than running out of icing and that didn’t happen with this kit. The instructions were easy to follow and the colors were so vibrant. It defiantly wowed at my granddaughter’s 6th birthday party. Oh, did I mention how delicious this cake was. So good!
    Date published: 2019-10-10
    Rated 5 out of 5 by from You can do this! This was a really fun activity and we involved all three of our kids. The most important ingredient: time. Give yourself a couple of days to do it right and be sure to read the directions a few days ahead so you have everything you need and have enough prep time to have some ingredients at “room temperature”. Also, it’s really good to refrigerate at certain times as the directions indicate. We had a very happy birthday girl when the final product was revealed!
    Date published: 2019-07-22
    Rated 5 out of 5 by from Fun to make, pretty to look at and delicious It was a lot of work but still fun. The directions didn’t have a baking temperature so I baked at 350. Don’t let anyone tell you everything you need is in the can - needed unsalted butter, milk, cream cheese and eggs. I used 2% milk and Neufchâtel cheese because that’s what I had and it came out great!
    Date published: 2019-06-23
    Rated 5 out of 5 by from Joy in a can! Made this cake with my kids a few days ago. It was so fun to make and it tasted delicious. Turned cut beautiful. Was much shorter than the picture but may be my error
    Date published: 2019-06-18
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  • What do you recommend for transporting this cake? 

    Asked by: Ang16
    HI Ang16, I just happened to make the Explosion Cake yesterday and transported it via car. I placed the cake on a 10" plate, stuck some toothpicks into the cake and draped plastic wrap over it. I then placed the cake into a tall cardboard box wide enough to fit my plate. So that it wouldn't shift side to side in the box, I placed kitchen towels on each side of the plate. I then placed the box on the floor behind my passenger seat and slide that seat back until it was snug with the box. We drove 5 miles away and the cake arrived at its destination with no issues.
    Answered by: Williams Sonoma
    Date published: 2019-12-26

    Hi.  My family doesn't prefer cream cheese frosting.  What can I use to replace the 12oz block of cream cheese?  Thank you 

    Asked by: ustrigirl
    Hi ustrigirl, You can substitute the cream cheese with equal amounts of butter.
    Answered by: Williams Sonoma
    Date published: 2019-12-22

    Can the cake be baked in two batches, so that I only have to have 3 pans, or will there be an issue with the second batch of batter having th sit on the counter for an hour?

    Asked by: Babz325
    Hi Babz325, We don't see an issue with baking 3 pans/layers at a time as it only takes 15-17 minutes to bake.
    Answered by: Williams Sonoma
    Date published: 2019-12-12

    Is it ok to use 8" pans? Will I need extra cake mix? I dont want to spend money on 6" pans when I have four 8". Advice is appreciated!

    Asked by: Jody
    Hi Jody, By using a larger diameter pan, if you don't have extra cake mix, then the cake layer will be much shorter. You will need to watch the baking time as well as it will bake much faster.
    Answered by: Williams Sonoma
    Date published: 2019-12-10

    Hello, is it okay to prebake the cake layers and freeze them? Then take out to thaw to room temp the day before?

    Asked by: scollinsrn
    Hi scollinsrn, Yes, you can prebake the cake layers and freeze them overnight. 1) Bake the cake and cool each layer on a wire cake rack. 2) Wrap each layer in plastic wrap. We suggest using two pieces to make sure it is covered well. 3) Wrap each layer with aluminum foil. 4) Place them in Ziploc bags (if they will fit) and place them in the freezer overnight.
    Answered by: Williams Sonoma
    Date published: 2019-11-10

    What is the shelf life of this cake and the accompaniments? I'm considering buying it now and making it a few months from now.

    Asked by: NIKKIB
    Hi NIKKIB, For the current batch we have available to ship, the best by date is November 2020.
    Answered by: Williams Sonoma
    Date published: 2019-10-21

    My husband threw away the directions to make the rainbow explosion cake!  I found the video but it doesn’t have the amount of unsalted butter etc. Help!

    Asked by: Alice
    Hi Alice, The kit includes all ingredients except : Cake: 1-1/2 sticks butter (unsalted), 1-1/3 cups milk, 3 large eggs (all at room temp) Frosting: 6 oz (1.5 sticks) unsalted butter, 12 oz cream cheese, (all at room temp)- will need a mixer with whisk.
    Answered by: Williams Sonoma
    Date published: 2019-07-15

    Can I use 6” round cake pans that are 3/4” tall? Or does it have to be 2” tall?

    Asked by: Allison
    Hi Allison, If you use anything shorter than 2" deep cake pans, we feel that it'll be difficult to handle the cake layers without them breaking apart as you're trying to stack them on top of each other.
    Answered by: Williams Sonoma
    Date published: 2019-12-18
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