Peak inside to discover the lucky rainbow cleverly disguised in a scrumptious St. Patrick’s Day bundt cake. This rainbow bundt cake is to die for!
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With St. Patrick’s Day right around the corner, I thought it would be fun to bake up something sweet and colorful. I came across this cake idea online and was determined to put my own twist on it and learn a new baking technique that creates a fun rainbow inside.
Although there is a trick to making this fun rainbow design, it is much easier than you’d expect.
I also thought it would be a nice break from all the green everything this upcoming holiday: green beer, green cupcakes, green eggs. I couldn’t possibly make another green dessert or drink to add to the list…
Thank goodness for the renowned Irish rainbows that are a common symbol for St. Patrick’s Day!
Additionally, this could also be used for a birthday party or for celebrating Pride month. It’s not strictly for the month of March. This luscious, rich cake needs absolutely no frosting or icing because it is just sweet enough on its own. The naturally buttery sweet flavor is out of this world!
Now, let me just get right to the point with the recipe and all the tips needed to make this fun, flavorful rainbow bundt cake…
Rainbow Bundt Cake
How do you make the fun rainbow design?
First, you’ll start by making the batter in one bowl. Then you’ll scoop out about ⅓ cup of batter each into four different bowls. These reserved bowls will be for four different colors: red, blue, yellow and green. Pour the regular batter (reserving ⅓ of it for the top) into the greased bundt cake pan and use a spoon to create a trench and spread some up the sides of the pan. This trench will be filled with all the rainbow colors! Start adding each food dye to each bowl of reserved batter. After mixing, add the first color into the trench. Repeat the same step of carefully spreading it up the sides just a little, making a trench for the next three colors. Repeat until you’ve used all the colors. Then top with the rest of the regular, uncolored cake batter.
What cake pan is best to use?
It is recommended by some to use a tube pan for best results. However, I’ll be completely honest with you and admit I used what I had on hand. I used a traditional fluted bundt cake pan and it still worked just fine. You can also use a ring mold if you prefer.
Tools You’ll Need | St. Patrick’s Day Rainbow Bundt Cake
Bundt cake pan
Large mixing bowl
Small bowls, 4
Whisk
Rubber spatula or wooden spoon
Measuring cups and spoons
Ziploc bags or piping bags
Spoons
Electric hand mixer
Scissors, optional
Rubber bands, optional
Ingredients | St. Patrick’s Day Rainbow Bundt Cake
Food coloring – Liquid food coloring is used to create the rainbow colors throughout the cake. Gel can be used instead, but you will need less of it to create the same vibrant colors.
Flour – All-purpose flour is recommended for this rainbow cake recipe.
Sugar – Granulated sugar is used to sweeten this tasty rainbow bundt cake.
Eggs – These are used to bind the batter together and give it a beautiful rise. Part eggs with yolk and part without are used for a slightly lighter cake color.
Butter – Room temperature butter is used to create a rich flavor and classic crumb to this slightly dense bundt cake.
Milk – The liquid of choice for this recipe is milk due to its protein content that will create a better structure and texture.
Salt – Table or sea salt enhances all the flavors.
Vanilla – Real vanilla extract is the way to go and gives a classic, wholesome flavor to this bundt cake.
Baking powder – Baking powder is used to create a soft lift in the cake as it bakes.
Shortening – This is used as a non-stick agent to prevent sticking to the bundt cake pan.
How to Make Rainbow Bundt Cake
Preheat oven to 350ºF. Grease the bundt pan with shortening and flour.
Cream the butter, sugar, salt, vanilla, and baking powder together in a large mixing bowl until light and fluffy.
Add one egg at a time, mixing until well combined. Repeat with the egg whites.
Sift the flour in and then add in the milk and mix completely.
In four bowls add ⅓ cup each of the cake batter. Then add 30 drops of each food coloring into separate bowls, mixing until well incorporated.
Spoon each colored batter into its own piping bag or ziploc bag. After filling the ziploc bag, secure with a rubber band and snip the end off.
Use about ¾ of the batter to fill the bundt cake pan. Reserve the rest for the top for later.
Spread the batter up the sides of the pan a bit, creating a trench in the middle.
Add your first color by piping it around the pan. Use a spoon to spread it up the sides a bit leaving a trench in the middle. Repeat with the last 3 colors.
Add the rest of the cake batter to the top and spread it smooth.
Bake at 350ºF for 50-60 minutes. The top will be a light golden brown and when lightly pressed will spring back. You can use a toothpick to check for doneness if you prefer.
Let cool for ten minutes before turning over and inverting it on a plate or cake stand.
Cool completely before slicing. Serve alone or with vanilla ice cream.
Tips for Success | St. Patrick’s Day Rainbow Bundt Cake
For best results, use shortening and flour to grease the sides of the bundt pan. I know some people like to use butter, but do keep in mind butter tends to brown and burn more. For this recipe, you want a nice, even light exterior–which is best achieved using shortening to grease.
Please, please, please let the pan cool for ten minutes before inverting. If you do it too soon, you risk it collapsing the warm, delicate cake. However, if you wait too long, you risk it sticking to the pan and ruining the outside of the cake.
If you want to try different colors than I’ve used, that’s perfectly fine. Do be sure to make them bright so they shine through.
Wait for the cake to cool completely for better slicing and a cleaner view of the rainbow hidden inside.
More Baking Inspiration
Easy Strawberry Muffins Recipe
Classic, Fluffy Cinnamon Rolls
Secret Rainbow Bundt Cake
Equipment
- bundt cake pan
- large mixing bowl
- 4 small bowls
- whisk
- rubber spatula or wooden spoon
- measuring cups and spoons
- ziploc bags or piping bags
- spoons
- electric hand mixer
- scissors optional
- rubber bands optional
Ingredients
- 2 whole eggs
- 4 egg whites
- 3 cups flour
- 3 sticks butter 1 1/2 cups
- 1 1/2 cups sugar
- 3/4 cup milk
- 1 tsp vanilla extract
- 1 1/2 tsp salt
- 1 tbsp baking powder
- 30 drops food coloring, per color
- shortening for greasing cake pan
Instructions
- Preheat oven to 350ºF. Grease the bundt pan with shortening and flour.
- Cream the butter, sugar, salt, vanilla, and baking powder together in a large mixing bowl until light and fluffy.
- Add one egg at a time, mixing until well combined. Repeat with the egg whites.
- Sift the flour in and then add in the milk and mix completely.
- In four bowls add ⅓ cup each of the cake batter. Then add 30 drops of each food coloring into separate bowls, mixing until well incorporated.
- Spoon each colored batter into its own piping bag or ziploc bag. After filling the ziploc bag, secure with a rubber band and snip the end off.
- Use about ¾ of the batter to fill the bundt cake pan. Reserve the rest for the top for later. Spread the batter up the sides of the pan a bit, creating a trench in the middle.
- Add your first color by piping it around the pan. Use a spoon to spread it up the sides a bit leaving a trench in the middle. Repeat with the last 3 colors.
- Add the rest of the cake batter to the top and spread it smooth.
- Bake at 350ºF for 50-60 minutes. The top will be a light golden brown and when lightly pressed will spring back. You can use a toothpick to check for doneness if you prefer.
- Let cool for ten minutes before turning over and inverting it on a plate or cake stand.
- Cool completely before slicing. Serve alone or with vanilla ice cream.
