Rainbow Sprinkles Cake - CakeWhiz

Rainbow Sprinkles Cake

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Use this step by step tutorial to make this quick and easy rainbow sprinkles cake. Great to serve at kids parties or even St.Patrick’s day!

I wanted to have this rainbow sprinkles cake tutorial ready on Monday but my little one has decided he would much rather be CRANKY and fussy than perhaps take a NAP or even sleep early at night.

That leaves mommy EXHAUSTED with barely any time to work on her postings…lol.

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As promised, I am sharing a cake today, dedicated to St.Patrick’s day.

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Normally, St.Paddy’s day treats are “green” or “boozy.” But, I DIDN’T want to do either of those!

That left me with only one choice… RAINBOWS and lots of COLORS!

Lately, I have been OBSESSED with colorful SPRINKLES.

Do you remember those sprinkle Easter bunny toppers from a few weeks ago? 

I thought those would be PERFECT for Patrick’s Day BUT this time, I added a rainbow topper!

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Yes! I know what you are thinking: “Has Abeer gone crazy? Doesn’t she know a rainbow has 7 colors and BROWN is NOT one of them?” LOL!

Trust me folks… I am fully aware of that that BUT thanks to my exhaustion and laziness, I decided to just use all the LEFTOVER fondants from previous projects.

That resulted in this wacky rainbow with 5 WEIRD colors: Red, Yellow, Dark blue, Brown and Light blue…hahaha.

Please feel free to use my tutorial to make a PROPER rainbow…hehe.

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To make this rainbow sprinkles cake, you will need the following SUPPLIES:

Mini chocolate cake
Homemade marshmallow fondant (in the colors of a rainbow)
Pizza cutter
Basic flower cutter
Wax paper

These are the INSTRUCTIONS:

Step 1:
Roll out marshmallow fondant in different colors.
Use a pizza cutter to cut out thin and even strips.  

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Step 2:
Place your first fondant strip on a sheet of wax paper.
Then, brush very little water at the edge of this strip. 

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Step 3:
Stick the next strip on this damp edge.
Brush water along the edge again and stick another strip.
Keep doing this until all your strips are stuck together. 

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Step 4:
Keep your strips aside. 
Roll out some fondant in any color you want (I used dark blue).
The length of this piece should be about the same as the length of your strips. 

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Step 5:
Brush some water on this piece.
Gently pick up your clustered strips and place them on top of this dark blue piece until it sticks into place.

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Step 6:
Use a pizza cutter to cut out the irregular sides and you will end up with a single rainbow strip.

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Step 7:
Use both your hands to gently curve this entire rainbow strip until it looks like an upside down “u”

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Step 8:
Use a pizza cutter to cut out the bottoms so they are straight.

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Step 9:
Now, let’s make clouds.
Roll out some light blue fondant and use a flower cutter to cut out 2 flower shapes. 
Then, use a knife to cut these flowers in half.  

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Step 10:
Brush some water on the bottom of the rainbow strip and stick the clouds in place.
Allow this rainbow to dry for about 24 hours OR until it gets hard. 

Tip: To speed up the drying process, you can use 50/50 or mix some tylose powder or a bit of gumpaste into your fondant.

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Once this rainbow is dry, flip it over and use some melted chocolate to stick toothpicks on both ends. This will make it easy to push the rainbow into your mini sprinkle cakes,

And that’s it… you are done with this easy rainbow sprinkles cake. 

By the way, my rainbow didn’t turn out as neat as I would have liked…

Halfway through making it, my son started crying and I left to look after him. In my hurry, I forgot to cover my fondant pieces. By the time I got back, those fondant strips had dried up a little, which led to tiny cracks and tears as I continued working. 

Here’s a little TIP for you: If you are ever taking a break in between your fondant work, cover your pieces in plastic (saran wrap) to prevent them from drying!

Well, that’s all for today my lovelies!

Have a great weekend and Happy St.Paddy’s Day!

24 comments on “Rainbow Sprinkles Cake”

  1. I love your little cakes. Now PLEASE tell me how you did such a flawless sprinkle job. I looked at this one and your bunny one and some of your others, but I don’t see it. : )

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