This Grapefruit Sour Cream Cake is amazingly moist, bright with citrus and tart from the sour cream. A delicious cake best served with coffee or tea!

Seeing that it’s Friday and all I thought we should celebrate with cake.

Grapefruit Sour Cream Cake Slice
A ruby red grapefruit cake to be exact.

grapefruit collage
Last Friday a big ol’ box of grapefruit was delivered to my front door. The box came a little damaged and dented (thanks delivery person!), but when I opened it up and saw those beauts all was forgotten. After I made this cake I squeezed one grapefruit and strained it into a glass and drank it. SO darn good!

While pending the arrival of my grapefruits I devised a plan on how I was going to go about making the cake part. I borrowed the recipe from this post and the technique from this post, did a little ingredient swapsies and *poof!* this beautiful cake (that sort of tastes a bit like Froot Loops #notevengonnalie)… was born.


For the cake you’ll need the usual: flour, sugar, salt, baking powder, eggs, milk ,{melted} butter. You’ll also need some sour cream and two grapefruits!


Start off by measuring 1 cup of sugar and pour it into a large bowl.

grapefruit sugar
Zest the grapefruits until you have two tablespoons and then add it into the sugar bowl. Use your fingers and rub the sugar into the zest until the texture feels like wet sand.

pink grapefruit
Cut the grapefruit in half. I used a juicer and then strained the freshly squeezed grapefruit juice until I had 3 tablespoons worth.

eggs, grape fruit juice, butter and mixed

Next, into the bowl with the grapefruit sugar, crack and add in two eggs, the grapefruit juice, add the melted butter and give it all a good whisk.

salt, bpowder and whisk

Then, in a smaller bowl, combine the flour, salt and baking powder. Give that a good whisk too, to break up and clumps and fluff it up a bit.

mix sour cream and milk

Next, in a small bowl or measuring cup stir together the half cup of sour cream and the two tablespoons of whole milk. This just makes adding to the batter more simple.

whisk and pour
Alternately add a third of the dry ingredients, then a third of the sour cream mixture until it’s all incorporated. Pour the cake batter into a lined loaf pan. Bake in a preheated 350 degree oven for 45 minutes or until a tester comes out clean. Do NOT over bake!

baked cake
Let the cake cool in the pan for 10-15 minutes before removing.

run your knife
Then run a knife along the edge touching the pan and then use the parchment paper to lift it out on to a wire rack to finish cooling. Now go do a load of laundry.

For the glaze, whisk 1 cup powdered sugar, 1 (heaping) tablespoon of sour cream and then thinned it out with some whole milk. Uhhh yeah try NOT to drink this stuff. I dare you.

Annnnnd then I drizzled it all over the cake. Boo-yah!

Grapefruit Sour Cream Cake Slice

Pink Grapefruit Sour Cream Cake


Grape Fruit Sour Cream Cake Bite

And devour! It’s cakes like this that I wish I had the metabolism of a twelve-year-old because I’d eat this whole thing in a nano second. Like one second there’s a beautiful cake just sitting there and then *poof!* it’s gone and the only evidence is the crumbs on my chin. Awww yeah… to be twelve again.

Enjoy! And if you give this Grapefruit Sour Cream Cake recipe a try, let me know! Snap a photo and tag me on twitter or instagram!

Grapefruit Sour Cream Cake Tops

My cookbook Simply Scratch : 120 Wholesome Homemade Recipes Made Easy is now available! CLICK HERE for details and THANK YOU in advance! 

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Yield: 12 servings

Ruby Red Grapefruit Sour Cream Cake

This Grapefruit Sour Cream Cake is amazingly moist, bright with citrus and tart from the sour cream. A delicious cake best served with coffee or tea!


  • 1 cup granulated sugar
  • 2 tablespoons grapefruit zest, from a ruby red grapefruit
  • 2 large eggs
  • 3 tablespoons ruby red grapefruit juice, freshly squeezed and strained
  • 1/3 cup unsalted butter, melted and cooled
  • cup unbleached all-purpose flour
  • 1 teaspoon kosher salt
  • 1 teaspoon baking powder
  • 1/2 cup sour cream
  • 2 tablespoons whole milk


  • 1 cup powdered sugar
  • 1 tablespoon sour cream
  • 1 to 2 tablespoons whole milk


  • Preheat your oven to 350° and line an 8x5 loaf pan with parchment paper, then spray with cooking spray.
  • In a large bowl combine the sugar and the two tablespoons of grapefruit zest. Use your fingers and rub the zest into the sugar until it resembles wet sand.
  • Add the two eggs, grapefruit juice and melted butter. Stir until those ingredients are incorporated.
  • In a separate bowl, combine the flour, salt and baking powder. Give it a good whisk to remove and clumps.
  • In a small bowl or measuring cup; combine the sour cream and milk and stir until combined.
  • Starting with the flour and ending with sour cream/ milk mixture. Alternate and a third of each until everything is mixed in well.
  • Pour the cake batter into the prepared pan and bake for 45 minutes or until a tester comes out clean. Let the cake rest in the pan for 10 minutes before running a knife along the edge and using the parchment paper to lift the cake out of the pan.
  • Let the cake cool completely on a wire rack. Mean while make the glaze by combining the powdered sugar, sour cream and thinning it out with the milk.
  • Drizzle the glaze over the cooled cake and let it sit to harden for a few minutes.
Serving: 1slice, Calories: 242kcal, Carbohydrates: 40g, Protein: 3g, Fat: 8g, Saturated Fat: 5g, Polyunsaturated Fat: 1g, Monounsaturated Fat: 2g, Trans Fat: 1g, Cholesterol: 50mg, Sodium: 253mg, Potassium: 58mg, Fiber: 1g, Sugar: 27g, Vitamin A: 276IU, Vitamin C: 2mg, Calcium: 46mg, Iron: 1mg

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Note: TexaSweet in no way compensated me for this post. They simply sent me a shipment of their glorious ruby reds out of the kindness of their hearts and I blogged about using it this Grapefruit Sour Cream Cake… it’s as simple as that. My opinions are my own and I love these grapefruits!