Grapefruit Cake with Marshmallow Buttercream

Grapefruit is a food I’m funny about; I don’t like it plain as it’s too tart for my tastes. But, I do like it in other things – like cake, for example. (Especially cake covered in marshmallow buttercream and topped with a blood orange glaze… I am so excited to share this recipe with you guys!
Grapefruit Cake with Marshmallow Buttercream

For some that means a glimmer of spring shines near off in the distance. For me (and other Texans), well, March arrived back in January. The trees are in bloom and even yesterday my mom and I saw some bluebonnets in full bloom, and bluebonnets never bloom until late March/April… Bleck, bleck, BLECK! (not bleck to the flowers, just the weather!)

I hate warm winters.

Oh, I know; if I lived somewhere where it snowed day after day and had to deal with winter depression I might not mind these warm winters so much, but all I’m asking for is a little balance. A small burst of cold for a few days, then maybe some sunshine and warmer (I don’t mean 60’s or 70’s, either) temperatures and then maybe a little cold again – balance, you know? To put it in the words of Pepi from Shop Around The Corner (best Christmas movie ever): Am I asking too much??

Ah, well – c’est la vie!

Since we’re on the subject of all things bright and sunshiny… where do we stand on Grapefruit?

All three components have me thrilled to pieces:

  1. We start with a buttermilk cake (once again, I love buttermilk cakes as they are usually moist and of course delicious) and give it a little edge by adding grapefruit zest as well as actual grapefruit chunks (if you don’t like the idea of the chunks, just leave them out – no big deal!).
  2. To decorate the cake, I made a marshmallow buttercream frosting – which, as a side note, has to be one of the only buttercream that I could eat by the spoonful. For the frosting, we’re making a basic buttercream and adding a whole jar(!) of marshmallow creme which turns it into pure deliciousness!
  3. To finish, I made a blood orange glaze – which turns into a lovely shade pink – for some tangy sparkle. The glaze consists of two ingredients: blood orange juice and powdered sugar. It’s really fun – wait, did I just say a glaze was fun? – and pretty; it adds the right amount of tang to compliment the cake but doesn’t overshadow any of the other flavors.

If you like citrus desserts and need a little sunshine, I highly recommend trying this cake. It’s pretty (I could so see this adorning a dessert table) and not hard at all to make. I’m excited about it and think you would be too!

If you try it, I would LOVE to know how you liked it – comment, send me a message, or SOMETHING, just let me hear from you! 😀

The lowdown: A buttermilk cake enhanced with grapefruit zest and actual chunks of grapefruit flesh is covered in a marshmallow buttercream and then finished with a blood orange glaze – the perfect cake to use up some winter citrus!
Grapefruit Cake with Marshmallow Buttercream
  • Serves 12

Grapefruit Cake:

  • 2 1/2 C. cake flour;
  • 1 tsp. baking powder;
  • 1/2 tsp. baking soda;
  • 1/2 tsp. salt;
  • 1 grapefruit;
  • 12 tbsp. (1 1/2 sticks) unsalted butter, softened, but not too soft!;
  • 1 1/2 C. granulated sugar;
  • 5 eggs, room temperature;
  • 1 C. buttermilk (I highly recommend using full fat buttermilk);
  • 1 tbsp. vanilla extract.

Marshmallow Buttercream:

  • 3 C. powdered sugar;
  • 1 C. (2 sticks) butter, softened;
  • 1 (7 oz) jar marshmallow creme (you could try fluff as well).

Blood Orange Glaze:

  • Juice of 1 blood orange (1/4 C.);
  • 1 1/2 C. powdered sugar.
If you enjoyed this recipe, you may like…

For the cake

  1. Preheat oven to 350° f.
  2. Spray three 8″ round pans with baking spray (this is the kind with flour in it) or grease and line bottoms with parchment paper.
  3. Zest grapefruit and set aside. Then, cut grapefruit in half and scoop out flesh, using the same method you would as if you were going to eat it. Place grapefruit chunks in bowl and set aside.
  4. In a medium sized bowl, sift together flour, baking powder, baking soda, and salt. Add in grapefruit zest, and using a slotted spoon to remove chunks from bowl (you will want to shake off excess juice), add grapefruit chunks. Toss to combine.
  5. In the bowl of a stand mixer fitted with the paddle attachment (or using a large bowl and handheld mixer), beat butter for about 30 seconds. Gradually add sugar and continue to beat for 2-3 minutes, or until light and fluffy.
  6. Add eggs one at a time, beating after each addition, scraping down bowl a few times as needed.
  7. Add 1/3 flour mixture and 1/3 of the buttermilk. Beat on low speed (or by hand) until just incorporated. Using a rubber spatula and mixing by hand, add vanilla and remaining flour and buttermilk in two batches. Scrape down sides of bowl as needed. The batter will look a little grainy, but that’s okay – just be sure you’ve mixed all of the big flour patches.
  8. Divide batter evenly between pans.
  9. Bake for 20-30 minutes or until a toothpick comes out with moist crumbs, or when when the tops of the cakes springs back when lightly pressed in the center.
  10. Transfer pans to a cooling rack and cool in pans for 1 hour, or until no longer warm.
  11. Once cooled, invert cakes onto racks (you may need to coax them by running a knife around the pans).
  12. While cakes continue cooling, make frosting. (Remember, that they already need to be pretty cool when you invert them, otherwise let them cool a bit longer before making the frosting).

For the frosting

  1. In a stand mixer fitted with the whisk (or paddle, see note below) attachment, cream together butter and sugar for 2 minutes.
  2. Add marshmallow creme and vanilla and beat for an additional 2 minutes.

To assemble

  1. Place one cake, top side down, on a cake stand (or whatever you want to decorate your cake on).
  2. Evenly spread about 1/2 C. of frosting on the first layer. Place second layer on top of first, again with the top side facing down. Spread with about another 1/2 C. frosting. Place 3rd layer on top of second, using the same top side down method.
  3. Cover the sides and top of cake with a very thin coating of frosting and freeze for 15 minutes. While freezing, place frosting in fridge.
  4. Remove cake from freezer and spread remaining frosting evenly around sides and top of cake.

Make the glaze

  1. In a small bowl, whisk together fresh blood orange juice and powdered sugar. Note: if you want a thicker glaze, add more powdered sugar, 1 tablespoon at a time, until it reaches your desired consistency.
  2. Pour glaze on top of cake and let drizzle down sides, using as much or little of the glaze as you would like – I didn’t use quite all of it.
  3. (Once you have finished decorating, you now have permission to lick any beaters and bowls clean…
  4. Serve cake immediately, or cover and keep in fridge until ready to serve. If keeping in fridge, bring to room temperature before serving.


For the frosting: I’m not sue if a regular paddle would work or not, but my brother gave me this awesome paddle attachment for our KitchenAid, (which I absolutely LOVE) and is what I used. This special paddle is super great; I now know creamed butter like I’ve never known it before! It has a rubber coating and a special feature that scrapes the sides of the bowl. Plus, it’s dishwasher safe – big win! If you are interested in checking it out, I’ve included a link at the bottom of this post below the recipe.
As a side note: I have not been paid or anything to tell you about this product. I just thinks it’s awesome and want to let you in on it!

Leave a Reply

Your email address will not be published.

Related Posts