Grapefruit Sour Cream Cake – Simply Scratch

This Grapefruit Sour Cream Cake is deliciously moist, bursting with bright citrus flavor and coated in a thick layer of sour cream icing. Yield 8 to 10 slices.

I’m not a huge dessert person, but when faced with a decision of chocolate or lemon (any citrus really), I’ll chose lemon every single time. Years ago I was gifted a box of ruby red grapefruits I had a little time before delivery to figure out what I was going to make using them.

The obvious answer was cake.

So I took inspiration from this lemon blueberry cake recipe and the technique from this mini cake recipe, did a little ingredient swap and this beautiful cake was born.

It’s citrusy, tangy, and in a way tastes like froot loops cereal – but in the best way. Because cake.

To Make The Grapefruit Sour Cream Cake You Will Need:

• unbleached all-purpose flour – Gives structure to the cake.
• fine salt – Enhances the flavor of the cake.
• baking powder – Will create lightness in the batter, which in turn, makes it rise.
• granulate sugar (white) – For sweetening and flavor.
• grapefruit zest and juice – Lends tart citrus flavor.
• eggs – Acts as a binding agent, helps the cake rise and adds rich flavor.
• unsalted butter (melted and cooled) – Adds moisture, richness and flavor.
• sour cream – Lends moisture and tangy rich flavor.
• milk – Adds moisture to the cake. Use any milk you prefer.

for the icing:

• powdered sugar
• sour cream
• milk

Preheat your oven to 350℉ (or 180℃).

Line a 8×5 loaf pan with parchment and spray with a nonstick baking spray.

Make The Cake:

In a medium bowl, measure and add 1-1/2 cups flour, 1 teaspoon fine salt and 1 teaspoon baking powder. Give that a whisk and set it off to the side.

In a large bowl, measure and add 1 cup of sugar and the zest of 1 ruby red grapefruit. Use your fingers and rub the sugar into the zest until the texture feels like wet sand.

Next, add in 2 large eggs, 3 tablespoons grapefruit juice and 1/3 cup melted (and cooled) butter.

Whisk well to combine.

Next, in a small bowl or measuring cup stir together 1/2 cup of sour cream and the 2 tablespoons of milk. Doing this makes adding to the batter more simple.

Beginning with the dry ingredients and ending with the sour cream mixture, alternate adding 1/3 of the dry ingredients and stirring just until combined.

Then add in 1/3 of the sour cream mixture, repeating until it’s all incorporated.

Pour the cake batter into a lined loaf pan and spread the top smooth. Bake in a preheated oven for 45 minutes or until a tester comes out clean. Do NOT over bake!

Let the cake cool in the pan for 10-15 minutes before removing and transferring to a wire rack to finish cooling.

Make The Icing:

Into a medium bowl, sift 1-1/2 cups powdered sugar. Whisk in the sour cream while thinning it out with 2-3 tablespoons of milk at a time. You want it thick but pourable.

Then drizzle it all over the cooled cake. Allow the icing to set before serving. You can pop it into the fridge to speed the process up a bit.

Slice.

Serve. And prepare yourself to fall in love!

How to Store Grapefruit Sour Cream Cake:

Transfer slices of the frosted cake to a storage container and refrigerate.

How To Freeze Grapefruit Sour Cream Cake:

Double wrap the unfrosted loaf in plastic wrap and then in aluminum foil. Thaw when ready to serve. Once the loaf has thawed, is when I  would recommend make the icing and drizzle it over the cake.

How Long Will This Grapefruit Sour Cream Last?

If stored properly, this cake will last up to 3 to 4 days if refrigerated and at room temperature or freeze for up to 3 months.