Ruby Red Grapefruit Sheet Cake with Grapefruit Cream Cheese Frosting is tender, moist, sweet, and tart. If you like citrus and grapefruit, this flavorful combination is sure to satisfy!
Ruby Red Grapefruit Sheet Cake with Grapefruit Cream Cheese Frosting
The perfect breakfast…er, because grapefruit is great for breakfast, am I right?
That’s my story and I’m sticking to it!
This cake is wonderfully dense and moist. The batter is very wet resulting in an almost brownie like cake.
It has a delightful citrus flavor that is clearly grapefruit. There’s no mistaking it for orange, lemon, or lime. It has a unique, mild grapefruit flavor. It’s actually a refreshing cake flavor that you grow to like more and more with every bite!
I smothered this cake in a smooth cream cheese frosting that has a kiss of grapefruit flavor. I used a basic Cream Cheese Frosting and added one tablespoon grapefruit zest to it. However, if you think this is too much grapefruit, you may choose to frost simply with the cream cheese frosting. You really can’t beat the classic!
Fresh grapefruit is available to me all year, so I consider this a year-round dessert. It makes a memorable and pretty cake for birthday celebrations as well as potlucks or entertaining.
Tips
- I recommend using real butter and not margarine.
- You can substitute sour cream or Greek yogurt for the buttermilk. You’ll use 1/2 cup for substitutions.
- Additionally, you can use a plain cream cheese frosting, like my Best Cream Cheese Frosting, if you’re concerned with grapefruit overload.
- You may also consider adding 1 cup chopped pecans, walnuts, or almonds to the cake batter.

Ruby Red Grapefruit Sheet Cake with Grapefruit Cream Cheese Frosting
Want to save recipes? Create an account or login & then you can use the “Save Recipe” button when viewing a recipe to save it to your Recipe Box. You can access your saved recipes on any device and generate a shopping list for recipes in your collections.
Save To Your Recipe BoxIngredients
CAKE
- 1 ruby red grapefruit 3 tablespoon zest, divided, and 1/2 cup juice from grapefruit. You will use 2 tablespoons zest in the cake and 1 tablespoon in the frosting.
- 1 cup butter melted
- 1/2 cup water
- 2 cups all-purpose flour
- 2 cups granulated sugar
- 1 teaspoon baking soda
- 1/2 teaspoon salt
- 1/2 teaspoon ground cinnamon
- 1/2 cup buttermilk
- 2 large eggs
- 1 teaspoon vanilla extract
FROSTING
- 8 ounces cream cheese at room temperature
- 1/2 cup butter at room temperature
- 1 teaspoon vanilla extract
- 4 cups confectioners sugar
- *1 tablespoon grapefruit zest from 3 tablespoons listed above
Instructions
- Preheat the oven to 375 degrees F.
- Spray a 9x13 inch sheet pan with non-stick spray or spread a thin layer of vegetable shortening inside the pan.
- Stir together the melted butter, 2 tablespoons grapefruit zest, and water.
- Add buttermilk, 1/2 cup grapefruit juice, eggs, extract, and butter mixture.
- Stir to combine.
- Pour batter into the prepared 9x13 inch pan.
- Bake 25 to 32 minutes or until wooden pick inserted in the center comes out clean.
- Cool 1 hour before frosting.
- FROSTING
- In the bowl of a mixture, combine cream cheese and butter until light and fluffy.
- Slowly add sugar.
- When sugar is incorporated, add 1 tablespoon grapefruit zest.
- Spread evenly over cool cake.
- Store in the refrigerator.
Notes
Nutrition
As an Amazon Associate, I earn from qualifying purchases. This post contains affiliate links. If you click the link and make a purchase I will receive a small commission at no cost to you. Visit all my recommended products at Paula’s Picks on Amazon. Read my entire Privacy Policy here.
You can also find great recipes here or at Meal Plan Monday or Weekend Potluck.
You may also like my Grapefruit Mojito and my Grapefruit Brulee recipe! Click the photo for the recipe.

Gentle Joy Homemaker says
Your cake looks and sounds wonderful… 🙂
Brenda says
The ingredient list says 1/2 cup grapefruit juice and then the instructions mentions 2T in the cake batter. Does the rest go elsewhere?
Paula says
Brenda, thanks for catching my error. I have it corrected now in the recipe. 1/2 cup juice and 2 Tablespoons zest goes in the cake. 1 tablespoon zest goes in the frosting. Sorry for the confusion. Paula
Brenda says
Thank you for your quick reply, I look forward to trying this!
Linda says
I totally agree a breakfast dessert with a healthy kick to start the day! This really sounds interesting. Everyone would be surprised to find grapefruit it their newest favorite cake! Thanks for sharing, Paula.
Wishes for tasty dishes,
Linda
Danae @ Recipe Runner says
People eat grapefruit for breakfast so I see no reason why I should have a slice of this cake! It looks so moist and delicious, totally worth running a few extra miles for. 🙂