Easy Rainbow Cake with Lemon Glaze
When I first started working on this easy rainbow cake recipe for my Beautiful Bundts cookbook, I wasn't sure the concept would work. Would the colors all blend upon baking and make one big embarrassing mess, or would they swirl beautifully? Luckily, it was the latter, and this vibrant, lemon glazed, vanilla cake became one of my favorite new recipes.
A Cheerful, festive Cake {And it's Easier than it looks!)
The great thing about this cake is that it looks super fancy, but it's easy enough for even novice bakers to make. My daughter Gigi made it at age 8 (because...rainbows and bright colors!), and she just needed a little supervision with spreading the rainbow layers. I've provided detailed photos and step by step instructions, below, to help you along the way.
This moist cake is perfect for a special occasion like a birthday party or St. Patrick's Day.....or for no occasion at all other than a love of cheerful colors, cake, and rainbows. The colors can also be altered to fit a celebration any time of year: red white and blue for July 4th; red, white and green for Christmas; purple, gold, and green for Mardi Gras. You get the idea.
Top Tips For Making Your Most magical Homemade Rainbow Cake
- Bake it ahead: With most of my Bundt recipes, I recommend baking the cake one day and then decorating and serving it the next day. This gives the cake crumb time to tighten, making it easier to slice. The best way get clean slices is with a sharp serrated knife.
- Use gel food coloring: There are different types of food colors--some gel and some liquid based. My favorite food coloring to use is the gel based ones, as they produce the most vibrant colors with the least amount of drops. Liquid colors require a larger quantity, which also dilutes the batter.
- Layer carefully: Although it takes a little time, make sure that you layer your colored batters carefully, one at a time, spreading as close to the edges of the pan as possible. That way you will end up with the colors of the rainbow, and not a big swirly, oddly colored mess!
Ingredients and Special Equipment
Please check the recipe card at the end of this post for specific quantities.
Rainbow Cake Ingredients
- All-purpose flour: Substitute an equal amount of your favorite gluten-free flour blend to make a gluten-free cake.
- Baking powder / baking soda
- Salt
- Unsalted butter: At room temperature to easily blend with the sugar and oil.
- Oil: Use any neutral oil, such as vegetable oil, canola, safflower, or melted coconut oil.
- Granulated sugar
- Large eggs: Also at room temperature.
- Vanilla extract
- Buttermilk: If you don't have buttermilk, make your own! For every cup needed, mix 15 tablespoon milk plus 1 tablespoon white or apple cider vinegar and let stand at room temperature for 15 minutes.
- Food coloring: Red, orange, yellow, green, blue and purple. See my "Top Tips," above, for more.
Lemon Glaze Ingredients
- Confectioners' sugar / powdered sugar: Also called "icing sugar."
- Lemon zest (optional)
- Lemon juice: Fresh or bottled. One medium lemon yields about 2-3 tablespoon (45 mL) juice, so you will need 2 lemons for this recipe.
Recommended Special Equipment
- 12-cup Bundt pan: A standard 12-cup Bundt pan, like the one shown above, is the best fit for the amount of batter in this recipe, and it has an easy shape for spreading the layers of batter.
- Nonstick baking spray: My #1 tool for preventing Bundts from sticking to pans!
- Stand mixer fitted with the paddle attachment: Or a hand mixer and a large mixing bowl.
- Small offset spatula: For spreading layers of batter in the Bundt pan.
- 6 small or medium bowls: For dividing and mixing the colored batters.
Step By Step Photos and Instructions
- Heat oven to 350℉. Spray a 12-cup Bundt pan with non-stick baking spray.
- In a medium bowl, whisk dry ingredients: flour, baking powder, salt, and baking soda.
- In the bowl of an electric mixer fitted with the paddle attachment, or using a hand mixer and a large bowl, beat the sugar, butter, and oil at medium speed for 4 minutes, or until light and fluffy, stopping to scrape the sides of the bowl with a rubber spatula as necessary.
4. Beat in the eggs, one at a time. Add the vanilla and beat at medium high speed for 1 minute more.
5. With the mixer on low speed, alternately beat in the flour mixture and the buttermilk, making three additions of flour and two of buttermilk, beating until incorporated.
6. Divide batter equally among 6 small bowls, about 1⅓ cups of cake batter per bowl. You can also leave one portion in the mixing bowl and only use 5 other bowls.
7. Stir enough red food coloring into the first bowl and stir to get a nice, even red batter (4 to 8 drops, depending on your food coloring.) Repeat with the other food colorings and batters.
8. Transfer the red batter to the prepared Bundt pan, spreading the first layer evenly using a spoon or an offset spatula. Repeat the process with the remaining batters in the following order: orange layer, yellow layer, green layer, blue layer, purple layer. Do your best to spread each color evenly without swirling into other colors, but expect a few imperfections!
9. Bake the Bundt in your preheated oven for 50-65 minutes, or until puffed and golden brown and a cake tester or toothpick inserted in the center comes out clean.
10. Let the cake cool in the pan for 10 minutes, then carefully invert the cake onto a wire rack to cool completely.
Glaze your Cake
- In a medium bowl, whisk confectioners' sugar, lemon zest, and 3 tablespoon lemon juice until smooth. Whisk in more lemon juice, 1 teaspoon at a time, until glaze is thick but pourable.
- Pour the glaze over the cooled cake, letting it drip down the sides of the cake. Let the glaze set for at least 15 minutes before serving.
Variations on This Rainbow Cake
- Layer cake vs. Bundt cake: If you prefer to make a rainbow layer cake instead of a Bundt, bake the colored batters in 6 round cake pans for 20-25 minutes (6 inch or 8 inch, although the 8 inch layers will obviously have less depth.) Most people don't have 6 identical cake pans, so you can bake the layers in batches.
- Add rainbow sprinkles: Give a hint of what the inside of the cake looks like by topping the outside of the cake with rainbow sprinkles.
- Different colors: Instead of orange, blue, green, yellow, purple and red layers, you can do theme colors based on a holiday (red, white and blue), school colors, or simply favorite colors. Just divide the batter equally depending on the number of colors.
- Topping variations: Instead of lemon glaze, you can do a plain vanilla white frosting / glaze, substituting whole milk for the lemon juice. A cream cheese glaze is another good choice!
Make Ahead and Storage Instructions
- Make ahead: You can prepare this cake up to 3 days in advance. Place the cooled cake on a cake plate covered tightly with plastic wrap. Store cake at room temperature or in the refrigerator and glaze before serving.
- Freezing: Freeze the whole cake for up to two months. Cool the Bundt completely, then wrap it tightly in plastic wrap and then aluminum foil. Seal the cake in a large freezer bag for an extra layer of protection. Thaw the cake in the refrigerator overnight before glazing.
Troubleshooting / Frequently Asked Questions
Why Didn't My Colors Look Like The Cake in The Photos?
Your baked Bundt colors might vary in appearance if you don't add enough food color to the batter, or if you use liquid food color vs. gel based colors (which require fewer drops to get vibrant colors.) A second reason is if you mix your colors too much while layering them in the pan. Using an offset spatula or the back of a spoon will help to spread the layers without blending the colors.
How do I prevent my Bundt From Sticking to the Pan?
I've baked hundreds of Bundts over the years, and my number one suggestion for preventing them from sticking to their pans is to use a nonstick baking spray (such as Pam for Baking or Baker's Joy.) These products contain a mix of flour and oils, mimicking the "butter and flour" method that was used for years before they hit the market. Use a pastry brush or a paper towel to ensure that your coat every crevice of your Bundt pan!
Why Did my Bundt Sink in the Middle?
There are a few key reasons why your Bundt might sink in the middle while baking:
- Overmixing incorporates too much air, causing the cake to deflate during baking.
- Baking at a lower temperature can prevent proper rising. Too high a temperature can cause edges to set too quickly, creating a sunken center. Check your oven temperature!
- Underbaking a cake leads to a gooey center that collapses when removed from the oven.
Bake some More of My Favorite "Beautiful Bundts!"
- Old-Fashioned Gingerbread Cake with Vanilla Creme Anglaise
- Mexican Chocolate Cake
- Pumpkin Bundt Cake with Brown Sugar Glaze
- Easy Bacon, Cheddar, and Jalapeno Cornbread
- The Perfect Old-Fashioned Pound Cake Recipe
Tried this recipe and loved it? Take a photo and tag me on Instagram or give it a review!
Rainbow Cake with Lemon Glaze
Equipment
- stand mixer fitted with the paddle attachment or handheld electric mixer
- 6 small bowls
Ingredients
Rainbow Cake
- 3 cups all purpose flour
- 2 teaspoon baking powder
- 1 teaspoon salt
- ½ teaspoon baking soda
- 2¼ cups granulated sugar
- 1 cup unsalted butter, room temperature
- ¼ cup canola, vegetable, safflower or melted coconut oil
- 4 large eggs, room temperature
- 1 tablespoon vanilla extract
- 1⅓ cups buttermilk
- red, orange, yellow green, blue, and purple food colors (see Notes)
Lemon Glaze
- 2 cups confectioners' sugar
- 1 teaspoon grated lemon zest (optional)
- 3-5 tablespoon lemon juice
Instructions
Bake the Rainbow Cake
- Preheat your oven to 350℉. Spray a 12-cup Bundt pan with non-stick baking spray.
- In a medium bowl, whisk together flour, baking powder, salt, and baking soda.
- In the bowl of a stand mixer fitted with the paddle attachment, or using a hand mixer and a large bowl, beat the sugar, butter, and oil at medium speed for 4 minutes, or until light and fluffy, stopping to scrape the sides of the bowl with a rubber spatula as necessary.
- Beat in the eggs, one at a time. Add the vanilla and beat at medium high speed for 1 minute more.
- With the mixer on low speed, alternately beat in the flour mixture and the buttermilk, making three additions of flour and two of buttermilk, beating until incorporated.
- Divide the batter equally among 6 small bowls (see Notes), about 1⅓ cups of batter per bowl. You can also leave one portion in the mixing bowl and only use 5 other bowls.
- Stir enough red food coloring into one bowl and stir to get a nice, even red batter (4 to 8 drops, depending on your food coloring.) Repeat with the other food colorings and batters.
- Transfer the red batter to the prepared Bundt pan, spreading evenly using a spoon or an offset spatula. Repeat the process with the remaining batters in the following order: orange, yellow, green, blue, purple. Do your best to layer each color evenly without swirling into other colors, but expect a few imperfections!
- Bake the Bundt in your preheated oven for 50-65 minutes, or until puffed and golden brown and a cake tester or toothpick inserted in the center comes out clean.
- Let the cake cool in the pan for 10 minutes, then carefully invert the cake onto a wire rack to cool completely.
Lemon Glaze
- In a medium bowl, whisk confectioners' sugar, lemon zest, and 3 tablespoon lemon juice until smooth. Whisk in more lemon juice, 1 teaspoon at a time, until glaze is thick but pourable.
- Pour the glaze over the cooled cake, letting it drip down the sides. Let the glaze set for at least 15 minutes before serving.
Notes
-
- I prefer gel-based food colors rather than liquid because it produces the most vivid colors. Colors vary in intensity, so you may need fewer or more drops to achieve your desired color.
- The most accurate way to evenly divide your batter is to weigh it. Using a kitchen scale, weigh an empty bowl, add all of the batter and subtract the original weight of the bowl. Divide this number by 6 to see how much batter should be placed in each small bowl.
