Grapefruit Cake (with Buttercream Icing)

This fresh grapefruit cake is soft, citrusy, and absolutely stunning with a zesty grapefruit buttercream frosting. It’s the perfect way to celebrate citrus season and the perfect dessert for warmer days ahead.

Table of Contents

• Why I Love This Recipe
• Ingredients
• Substitutions and Variations
• Instructions
• How to Store & Make Ahead
• Other Loaf Cake Recipes You’ll Love
• Final Thoughts
• Connect With Me

This grapefruit cake is soft, light, and just sweet enough. It’s made with fresh grapefruit juice and zest for a vibrant, sunny flavor that shines in every bite. Baked in a simple loaf pan and topped with grapefruit buttercream icing, it’s easy enough for a casual weekend bake but elegant enough to serve at brunch, dinner parties, or spring and summer celebration. If you’ve been looking for a grapefruit cake recipe that’s bright, tender, and truly citrus-forward, this is it!

Why I Love This Recipe

As someone who adores baking with citrus, this recipe is one I find myself returning to each spring. While lemon gets all the love, grapefruit has a unique floral tartness that adds such depth and elegance to baked goods. I created this cake during a stretch of recipe testing that was all about celebrating seasonal ingredients in unexpected ways.

The inspiration? A bowl of ruby red grapefruits sitting on my counter and a craving for something light but indulgent. The result was this grapefruit loaf cake. It’s rich and buttery, but perfectly balanced by the tang of fresh grapefruit juice and zest. I love serving loaf cakes like this at dinner parties since it’s impressive and can be cut up into 10 slices.

Ingredients

Let’s take a quick look at what makes this cake so special. It’s made with pantry staples, plus a few key ingredients that elevate the flavor:

• Grapefruit Zest & Juice (3 tbsp each): Use fresh grapefruit if possible. It gives the cake brightness and subtle bitterness that balances the sweetness. Ruby red or pink grapefruits work beautifully for this cake!
• Flour (1 ¾ cups): All-purpose flour keeps the crumb light and tender.
• Butter (½ cup, softened): Adds richness and moisture.
• Eggs (2, room temperature): Help bind the batter and add fluffiness.
• Sugar (¾ cup): Just enough to sweeten without overpowering the citrus.
• Milk (½ cup): You can use dairy or your favorite plant-based milk.
• Vanilla Extract (1 tsp): Rounds out the flavor and complements the grapefruit.
• Baking Powder + Baking Soda: A combo of both gives the perfect rise and texture.

For the Grapefruit Buttercream

• Butter, icing sugar, grapefruit juice + zest, and a splash of milk make for a lusciously smooth frosting that enhances the cake’s citrus notes.

Substitutions and Variations

• Make it dairy-free: Use plant-based butter and milk.
• Add Greek yogurt: Swap ¼ cup of the milk for plain Greek yogurt for a little tang and a moist crumb.
• Try blood orange or lemon: If you’re out of grapefruit, lemon or blood orange would be lovely alternatives.
• Make it gluten-free: Use a 1:1 gluten-free flour blend. Add 1 extra tablespoon of milk if needed.
• Skip the frosting: This cake is delicious on its own or with a simple citrus glaze (mix powdered sugar + grapefruit juice).

Instructions

1. Preheat oven to 325°F. Grease and line a loaf pan with parchment paper.
2. In a bowl, whisk together flour, baking powder, baking soda, and salt.
3. In a separate large bowl, cream butter and sugar until light and fluffy.
4. Add eggs one at a time, mixing well. Stir in milk, vanilla, grapefruit zest, and juice.
5. Gradually mix in the dry ingredients until just combined. Do not overmix.
6. Pour batter into prepared loaf pan and smooth the top.
7. Bake for 50–55 minutes, or until a toothpick comes out clean.
8. Let the cake cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
9. Make the frosting: Beat butter until fluffy, then add icing sugar, grapefruit juice, milk, zest, and salt. Mix until smooth and spreadable.
10. Once the cake is completely cool, frost with the buttercream. Garnish with extra zest or candied grapefruit peel if desired.

How to Store & Make Ahead

• Store leftovers: Keep in an airtight container at room temperature for 2–3 days, or refrigerate for up to 5 days.
• Freeze it: Wrap the unfrosted loaf tightly in plastic wrap and freeze for up to 2 months. Thaw and frost before serving.
• Make ahead: You can bake the loaf and prepare the buttercream a day in advance. Store the cake at room temp and the frosting in the fridge, then assemble before serving.

Other Loaf Cake Recipes You’ll Love

• Blueberry Loaf Cake with White Chocolate
• Best Glazed Orange Loaf Cake Recipe
• Raspberry and White Chocolate Loaf Cake Recipe
• The Best Lemon, Blueberry, and Mint Loaf Cake

Final Thoughts

This grapefruit cake is a delicious way to bring a little sunshine into your kitchen. With a soft crumb, tangy citrus flavor, and the dreamiest grapefruit buttercream, it’s one of those bakes that feels both simple and sophisticated. Whether you’re baking for a spring brunch, a special occasion, or just because—it’s a refreshing treat that always impresses.

Connect With Me

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