Are you looking for the best birthday cake idea? Then why not go for a delicious rainbow cake, which adds more pop and color to any party. Not only are they optimal for birthdays, but they can also give life to any party, may it be a simple sit-down dinner or a celebration with loved ones. And while you might think a rainbow cake is hard to do because of the multiple-colored layers, it’s very easy and straightforward to follow, as long as you have the right ingredients and follow the steps correctly. So if you’re wondering about how to make a rainbow cake, read on as I show you the effortless way to make the best out of this deliciously beautiful cake!

How to Make a Colorful Rainbow Cake
Ingredients
For the cake:
- Unsalted butter for the pans
- 2 1/4 cups of granulated sugar
- One cup of vegetable oil
- Four large eggs
- Two teaspoons of vanilla extract
- 3 3/4 cups of all-purpose flour
- 3/4 teaspoon of baking soda
- Half a teaspoon of salt
- 1 1/2 cups of buttermilk
- Red blue, green, and yellow gel food coloring
For the frosting:
- Eight sticks of unsalted butter at room temperature cut into small pieces
- Pinch of salt
- Ten cups of sifted confectioners' sugar
- Two tablespoons of vanilla extract
- Eight tablespoons of milk
- Strawberries cut into slices (for garnishing)
Instructions
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Let's start with making the cake. Place the rack in the lower third of your oven, preheating it to 350 degrees F. Butter four nine-inch round pans, lining it with parchment paper.
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Mix both the sugar and vegetable oil in a bowl, beating it with a mixer on medium-high speed until it's thick and creamy. This will take about three minutes. Beat in the eggs after, one at a time. Add the vanilla as well then beat it all on high speed for two minutes or once the batter is fluffy and light.
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Sift the dry ingredients (salt, flour, and baking soda) in a separate bowl. Mix it on low speed. In the bowl of the sugar mixture, beat in the flour mixture and buttermilk alternatively (in three additions), starting and ending with the flour mixture.
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Divide the batter into four bowls, tinting each one with the four different colors. Pour it into the four different pans after.
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Bake the cake two pans at a time for 15 minutes, or if you prick a toothpick in the center and once taken out, it becomes clean. Let the pans cool for 15 minutes after and prepare the frosting while doing so.
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Make the frosting by beating the butter and salt in a bowl with the mixer on medium speed. Beat it for about two minutes or until the mixture is fluffy and smooth. Add in the confectioners' sugar gradually until it is smooth again, then add the vanilla. Place the speed on medium high, beating it until the mixture is thick, which would take about two minutes. Add the milk a little at a time and continue to beat it until the frosting is now spreadable.
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Assemble the cake by spreading about a cup and a half of frosting between each cake layer, covering the outside of the cake using the frosting leftover. Pipe the remaining frosting on the ends of the cake and top it with a small strawberry slice.
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Serve and enjoy!

You might also interested in my homemade ricotta cheese
In Conclusion Whether you’re a beginner or advanced baker, you’ll be able to create a rainbow cake effortlessly and even have your children help you out. Not only will they love the colorful flavors, but they’ll have the time of their lives as they participate in creating their cake, a start of their love for baking. I hope that this article on how to make a rainbow cake helped you become more knowledgeable about what to do when making this attractive and unique cake. So don’t wait any longer and whip this up on a whim for your loved ones to appreciate today. If you have any questions or would like to share your tips and experiences on making a rainbow cake to avoid any baking mistakes, then comment down below. I would love to hear what you have to think.
Author bio: Claire is the founder of SumoChef, and her passion is cooking. Her unique approach to cooking is the result of her varied experience and travel abroad. She believes that food is what actually unites people and the dining table is where we set aside our differences. SumoChef is where she finds expression to her passion and she hope be able to contribute to your cooking experience through this. Be sure to follow her on Facebook, Twitter, Instagram
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Diana, you are amazing! i met you at the FBC conference and we chatted about your upcoming road trip. you mentioned being off work due to some health concerns but i had no idea the extent of what you went through. just wanted to tell you that i admire your strength and resilience! all the best
thanks Eleanore. That’s extremely kind of you to say. One foot in front of the other and keep on smiling. 🙂