Watermelon Cake Recipe

This adorable Watermelon Cake is frosted with buttercream to look like a watermelon and it actually has watermelon baked inside it!

We’ve all seen recipes for cakes made with applesauce or mashed bananas and now it’s time for a cake with watermelon in it! It’s a fun cake to bring to all of your summer celebrations!

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Where is the watermelon cake recipe? In this post, I will share step-by-step instructions with photos for how to make the cake, as well as answering FAQs about the recipe and sharing a short video showing the recipe in motion. But you can go directly to the recipe by scrolling down to the bottom of the post.

How To Make A Watermelon Cake

Step One: Watermelon Puree

You’ll need one cup of watermelon puree/juice for this recipe so cut up about 1 1/2 cups of watermelon and puree it in the blender or food processor.

Here’s how to cut a watermelon as well as some very cool watermelon slicers.

Step 2: Cake Batter

For the watermelon cake batter, the ingredients are similar to those on the cake mix package but instead of water this recipe uses the pureed watermelon.

To intensify the watermelon flavor, I added a packet of watermelon Kool-Aid! If you can’t find watermelon Kool-Aid in your area, you can use watermelon Jello or even LorAnn watermelon flavoring.

Or skip the added flavor and just use the watermelon puree.

This is what the cake batter looks like with the puree and Kool-Aid. To get a more intense watermelon color, add a dollop of red gel paste or red food coloring.

Grease two 9-inch cake pans and line the bottom with parchment paper. Divide the cake batter between the two cake pans putting about two cups in each pan. Bake the cakes and cool completely.

Step 3: Frosting the Cake

While the cakes are cooling, make the buttercream frosting and tint some of pink and some green, leaving a little of the frosting white.

Use a long serrated knife to level the cooled cakes.

Put one layer of the cake on a cake round, stand or platter. Top with pink buttercream frosting.

Top with the second cake layer and use an offset spatula to frost the outside edges of the cakes with the green buttercream frosting.

Then, frost the top of the cake with the remaining pink buttercream.

Put the white buttercream frosting in a pastry bag or large ziptop bag and cut the tip. Pipe a line of white frosting along the edge of the cake where the pink and green buttercream meet.

Use an offset spatula to smooth out the white buttercream, if desired.

Randomly place chocolate chips, with the pointed tip downwards, on the top of the cake to look like watermelon seeds.

Watermelon Cake Recipe FAQs

1. Can I make this cake in a 9×13-inch instead of two 9-inch pans? Yes, you can make it in a 9×13-inch pan. It will take about 3-5 minutes longer to bake.

2. How can I make this cake without the watermelon puree? You can substitute one cup of watermelon puree with one cup of water.

3. Wondering how to store watermelon cake? Wrap the cake with plastic wrap and store in the fridge.

4. How long does watermelon cake last? Wrapped watermelon cake will last 3-4 days in the fridge.

Obsessed With All Things Watermelon?

Watermelon Salsa: This watermelon salsa recipe is so fun when served from a watermelon bowl! It is delicious with chips or on top of grilled chicken, salmon, or tacos.

How To Pick A Watermelon: Choosing the best watermelon is easy if you remember the 5 S’s for How To Pick A Watermelon: Spot, Stem, Sound, Scale, and Skin.

Watermelon Sorbet: Keep cool with this easy watermelon sorbet from A Kitchen Addiction.

Continue to Content

Watermelon Cake

Yield: 16

Prep Time: 20 minutes

Cook Time: 30 minutes

Total Time: 50 minutes

This adorable Watermelon Cake is frosted with buttercream to look like a watermelon and it actually has watermelon baked inside it!

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Ingredients

• 1 1/2 cups watermelon, (1 cup watermelon puree)
• 15.25 oz white cake mix
• 3 large eggs
• 1/3 cup vegetable oil
• .15 oz watermelon Kool-Aid, (optional)
• 2 1/2 cups buttercream frosting
• Red and green food coloring or gel paste
• 1/4 cup chocolate chips

Instructions

1. Preheat oven to 350˚F. Grease two 9-inch cake pans and line bottom with parchment paper. Set aside.
2. Puree the watermelon cubes and measure out one cup of watermelon puree.
3. Put the cake mix, watermelon puree, eggs, vegetable oil, and watermelon Kool-Aid (if using) in a large mixing bowl. Mix for 30 seconds on low and then beat for 2 minutes at medium speed.
4. Divide batter between two cake pans.
5. Bake at 350˚F for 29-33 minutes. Cool for 20 minutes in the pan, remove the cakes from the pan and then cool completely on a rack.
6. Tint about 1 1/2 cups of the buttercream pink, about 3/4 cup green, and leave 1/4 cup white.
7. Place one cake on a cake round or cake stand. Frost top with about 3/4 cup of pink frosting. Add the second cake and frost the outside edges with green buttercream and then the top with the remaining pink buttercream. Put the white buttercream in a pastry bag (or ziptop bag) and snip the corner. Pipe the white frosting along the edge of the cake.
8. Press chocolate chips into the top of the cake.

Nutrition Information:

Yield: 16 Serving Size: 16 Servings
Amount Per Serving: Calories: 321 Saturated Fat: 6g Cholesterol: 40mg Sodium: 269mg Carbohydrates: 49g Fiber: 1g Sugar: 36g Protein: 3g

Nutrition data is calculated automatically by Nutritionix and isn't always accurate. I am not a certified nutritionist and make no claims to the contrary. Each individual’s dietary needs and restrictions are unique to the individual. You are ultimately responsible for all decisions pertaining to your health.