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This Lemon and Grapefruit Buttermilk Bundt Cake is one of the absolute best-tasting cakes I’ve made.  It’s infused with lemon zest and the juices of both grapefruit and lemon.
A grapefruit glaze is poured over the top of the cake after it’s baked which gives the cake an incredibly moist crumb. To further enhance the bold citrus flavor, a lemon icing is drizzled over the top.

An overhead view of Lemon Grapefruit Buttermilk Cake topped with white icing next to a large bowl of grapefruits and oranges

This gorgeous lemon and grapefruit buttermilk cake features the perfect balance of tart and sweet. It is a wonderfully tender and aromatic cake that is finished with an incredible glaze which is poured over the top after the cake has baked.

Why This Recipe Works

  • This luscious lemon cake is the perfect size.
  • This lemon and grapefruit cake is ultra moist with a wonderful lemon flavor.
  • It’s delicious for breakfast, dessert, or a snack.

Ingredient Notes

See recipe box below for ingredient amounts and full recipe instructions. 

  • Flour: Use all-purpose flour (plain flour).
  • Baking powder: This ingredient helps the cake rise.
  • Sugar, salt, lemon zest, vanilla, grapefruit juice, and lemon juice: These ingredients provide excellent flavor.
  • Butter: Use salted butter. Make sure the butter is soft, not melted. A good way to check to see if your butter is the right consistency is to make an indention in the butter with your finger. If it’s easy to make an indentation and the butter keeps its shape, then it’s the correct temperature.
  • Eggs: Eggs provide structure in cakes.
  • Buttermilk: Buttermilk is creamy, tangy, and makes baked goods extremely moist. It is a key ingredient in this cake recipe. Buttermilk also reacts to the baking soda which helps the cake to rise.

Drizzling white icing onto the top of a Lemon and Grapefruit Buttermilk Cake next to a large bowl of oranges and grapefruits and half of a grapefruit on a small plate

How To Make This Recipe


  1. Whisk, flour, baking powder and salt together in a medium bowl. Set aside.


  2. Combine sugar, lemon zest and butter together in a large bowl.


  3. Add in the eggs, one at at time, beating after each addition and scraping down the bowl with a rubber spatula as needed.


  4. Add in the vanilla and the juices and continue mixing for about 30 seconds longer.


  5. Reduce mixing speed to low and add dry ingredients in 3 additions, alternating with buttermilk in two additions, beginning and ending with dry ingredients.


  6. Pour into prepared pan and bake for 45-50 minutes or until toothpick inserted in the center of the cake comes out clean.


  7. Place the pan on a cooling rack and cool, about 30 minutes.

To Make The Glaze


  1. Combine 1/3 cup of grapefruit juice with 1/3 cup sugar in a small saucepan and cook over low heat until the sugar dissolves.


  2. Spoon the grapefruit syrup over the cake.

To Make The Icing


  1. Whisk together the powdered sugar and the lemon juice until smooth. (If the icing seems too dry, add a little more lemon juice. It the icing appears to watery, add a tiny bit more powdered sugar until the desired consistency is achieved).


  2. Drizzle icing over the top of the cake.

  3. Serve

Expert Tips

  • Cream the butter and sugar together until light and fluffy for a smooth, velvety texture.
  • Don’t scoop the flour with a measuring cup. Instead, stir the flour first to loosen it and then spoon it into a dry measuring cup and level it off using the flat edge of a knife.
  • Check to make sure your oven is the proper temperature. It’s common for an oven to not be calibrated properly. Many ovens heat too high or too low compared to what the temperature is set at. I recommend investing on an oven thermometer to test your own oven temperature.
  • Feel free to make the glaze thicker by adding more powdered sugar or thinner by adding more juice.

Frequently Asked Questions

How Do You Store A Lemon And Grapefruit Cake?

You may refrigerate the cake overnight, or up to 3 days, covered with plastic wrap or in an airtight container.

What Should I Add As A Topping To The Lemon And Grapefruit Cake?

Although the cake is incredibly delicious on its own, you might like to add a dollop of homemade whipped cream or a scoop of vanilla ice cream.

Other Cake Recipes

Drizzling white icing onto the top of a Lemon and Grapefruit Buttermilk Cake next to a large bowl of oranges and grapefruits and half of a grapefruit on a small plate

Enjoy!


Lemon and Grapefruit Buttermilk Bundt Cake

Prep: 20 minutes
Cook: 55 minutes
Total: 1 hour 15 minutes
Servings: 8 servings
Lemon and Grapefruit Buttermilk Cake, infused with lemon zest and the juices of both grapefruit and lemon, topped with a citrus glaze and lemony icing.

Ingredients 

  • 3 cups all-purpose flour
  • 1 tablespoon baking powder
  • 1 1/2 teaspoon kosher salt
  • 3 cups sugar
  • 2 tablespoons lemon zest
  • 16 tablespoons butter , softened
  • 4 eggs
  • 1 teaspoon vanilla
  • 3 tablespoons grapefruit juice
  • 2 tablespoons lemon juice
  • 1 cup buttermilk

GLAZE

  • 1/3 cup grapefruit juice
  • 1/3 cup sugar

ICING

  • 1 cup powdered sugar
  • 2 tablespoons lemon juice

Instructions 

  • Preheat oven to 350 degrees F.
  • Spray the inside of a bundt pan with cooking spray and set aside.
  • Whisk, flour, baking powder and salt together in a medium bowl. Set aside.
  • Combine sugar, lemon zest and butter together in a large bowl.
  • Add in the eggs, one at at time, beating after each addition and scraping down the bowl with a rubber spatula as needed.
  • Add in the vanilla and the juices and continue mixing for about 30 seconds longer.
  • Reduce mixing speed to low and add dry ingredients in 3 additions, alternating with buttermilk in two additions, beginning and ending with dry ingredients.
  • Pour into prepared pan and bake for 45-50 minutes or until toothpick inserted in the center of the cake comes out clean.
  • Place the pan on a cooling rack and cool, about 30 minutes.
  • Carefully invert the cake onto rack; remove pan and let cake cool completely.
  • While the cake is cooling, prepare the glaze.
  • TO MAKE THE GLAZE
  • Combine 1/3 cup of grapefruit juice with 1/3 cup sugar in a small saucepan and cook over low heat until the sugar dissolves. Spoon the grapefruit syrup over the cake.
  • TO MAKE THE ICING
  • Whisk together the powdered sugar and the lemon juice until smooth. (If the icing seems too dry, add a little more lemon juice. It the icing appears to watery, add a tiny bit more powdered sugar until the desired consistency is achieved).
  • Drizzle icing over the top of the cake.
  • Serve.

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5 from 3 votes

36 Comments

  1. Oh, this sounds delicious! I love the lemon and grapefruit combo.

  2. Wish I was there for all the testing and retesting! 😀 I’m also crazy about citrus desserts and this beautiful cake would definitely feed my obsession!

  3. I just love anything citrus! And cake 🙂 This looks amazing!

  4. Sometimes I feel like poor grapefruit gets the short shrift; it doesn’t show up near enough in recipes compared to it’s cousins lemon and lime. And I love it…so I will remember this, I’ve got a pink one in the fridge now that needs to be used soon so now I’m thinking cake!

    1. Thanks, Barbara and you’re right – I don’t see very many recipes using grapefruit and I love the taste too.

  5. I probably would have wanted to try this even if you hadn’t perfected it so perfectly…just the thought of tangy buttermilk and bright citrus makes me hungry. Plus, it’s beautiful!

  6. This looks and sounds amazing! Oh, how I wish I had a piece right now with my morning coffee!

  7. Looks really decadent. I love all the grapefruit. And that pan is gorgeous. How nice to have a big kitchen!

  8. I think this is probably the prettiest bundt cake I’ve ever seen! Love the bright flavors of citrus here.