The Strawberry Rhubarb Layer Cake is a delightful treat that combines the sweet juiciness of strawberries with the tangy kick of rhubarb in every bite. Soft, fluffy cake layers are filled and topped with a luscious strawberry-rhubarb compote and creamy frosting, making it a perfect balance of fruity and rich flavors. The colors alone—a pretty pink and fresh green—make this cake a cheerful centerpiece for any gathering.
I love how this cake brings a little bit of spring and summer to the table, even if it’s still chilly outside. The rhubarb adds a bright, slightly tart note that keeps the sweetness from becoming too much, and the strawberries add that familiar, comforting fruitiness I always look forward to. When I make this cake, I make sure to use fresh, ripe strawberries and tender rhubarb stalks for the best flavor—it really makes a difference!
One of my favorite ways to serve the Strawberry Rhubarb Layer Cake is chilling it just enough so the frosting holds its shape but isn’t too stiff. It’s so great for celebrations like birthdays or a weekend get-together because it feels special without being fussy. Plus, guests always ask for the recipe after tasting it, so you know you’ve made something memorable. This cake has become a sweet tradition for me whenever strawberries and rhubarb are in season.
Key Ingredients & Substitutions
Rhubarb: Rhubarb gives the filling its signature tart flavor. If you can’t find fresh, frozen rhubarb works well too—just thaw and drain excess water. For a milder tartness, reduce the amount slightly.
Strawberries: Fresh, ripe strawberries bring sweetness and color. If strawberries aren’t in season, frozen are a fine substitute—just thaw before cooking. You can also swap for raspberries or cherries for a different fruit twist.
Buttermilk: Buttermilk keeps the cake moist and tender. If you don’t have buttermilk, mix 1 cup milk with 1 tablespoon lemon juice or vinegar and let sit for 5 minutes before using.
Butter: Use unsalted butter to control salt in the cake and frosting. Make sure it’s softened for easier mixing and better texture.
Cornstarch: This thickens the fruit filling nicely without changing flavor. If you prefer, arrowroot powder or tapioca starch can be swapped in the same amount.
How Do You Get the Fruity Filling Just Right?
Making the strawberry rhubarb filling with a juicy but thick texture is key. Here’s how I do it:
- Combine chopped rhubarb, strawberries, sugar, cornstarch, and lemon juice in a saucepan.
- Cook over medium heat and stir often to stop the mixture from sticking or burning.
- Once it thickens and the fruit softens (about 8-10 minutes), remove it from heat.
- Let it cool completely before using it between cake layers—this helps it set and not soak into the cake too much.
If your filling looks too watery, keep cooking a little longer or add a tiny bit more cornstarch mixed with water. For a chunkier texture, cook less time.
Equipment You’ll Need
- Mixing bowls – I use a set of size options to easily combine ingredients and save time.
- Electric mixer or whisk – makes beating the cake batter and frosting much easier and faster.
- Cake pans (3 x 8-inch) – I prefer these for even layers that are easy to stack and frost.
- Saucepan – for cooking the fruit filling; a sturdy one helps prevent sticking.
- Cooling racks – to cool the cake layers quickly and evenly for stacking.
- Spatula and offset spatula – for spreading filling and frosting smoothly over the cakes.
- Cake stand or serving plate – to display and serve the beautifully layered cake.
Flavor Variations & Add-Ins
- Swap strawberries with raspberries or cherries for a different fruity flavor or color.
- Add a layer of cream cheese or mascarpone frosting for extra richness.
- Mix in chopped nuts, like almonds or pistachios, into the frosting for added crunch.
- Garnish with fresh mint or edible flowers for a pretty, spring-like look.
Strawberry Rhubarb Layer Cake
Ingredients You’ll Need:
For the Cake:
- 2 ¾ cups all-purpose flour
- 2 ½ tsp baking powder
- ½ tsp baking soda
- ½ tsp salt
- ¾ cup unsalted butter, softened
- 1 ¾ cups granulated sugar
- 3 large eggs
- 2 tsp vanilla extract
- 1 cup buttermilk
For the Strawberry Rhubarb Filling:
- 2 cups chopped rhubarb
- 2 cups chopped strawberries
- ¾ cup granulated sugar
- 2 tbsp cornstarch
- 1 tbsp lemon juice
For the Frosting:
- 1 cup unsalted butter, softened
- 4 cups powdered sugar
- ¼ cup heavy cream
- 1 tsp vanilla extract
- Pinch of salt
- Optional: a few tablespoons of reserved strawberry rhubarb compote for flavor and color
How Much Time Will You Need?
This recipe takes about 30 minutes to prepare the filling and cake batter, 25-30 minutes to bake, and about 20 minutes to make the frosting. Add extra time to chill the filling and the assembled cake, about 30 minutes or more. In total, plan for roughly 2 to 2 ½ hours from start to serving.
Step-by-Step Instructions:
1. Preparing the Strawberry Rhubarb Filling:
In a medium saucepan, combine the rhubarb, strawberries, sugar, cornstarch, and lemon juice. Cook over medium heat, stirring often, until the mixture thickens and the fruit softens—about 8 to 10 minutes. Remove from heat and let cool completely. Save a small amount if you’d like to swirl it into the frosting for a fruity pink touch.
2. Baking the Cake Layers:
Preheat your oven to 350°F (175°C). Grease and flour three 8-inch cake pans. In a bowl, whisk together the flour, baking powder, baking soda, and salt. In a large bowl, beat the softened butter and sugar until light and fluffy. Add eggs one at a time, beating well after each. Stir in vanilla extract. Alternate adding the dry ingredients and the buttermilk to the butter mixture, starting and ending with the dry ingredients. Mix just until combined—don’t overmix!
Divide the batter evenly among the pans and bake for 25 to 30 minutes, or until a toothpick inserted in the center comes out clean. Let cakes cool in pans for 10 minutes, then transfer to a wire rack to cool completely.
3. Making the Frosting:
Using a mixer, beat softened butter until creamy. Gradually add powdered sugar on low speed, then add heavy cream, vanilla, and salt. Beat on high for 3 to 5 minutes until fluffy. If you like, gently fold in a few tablespoons of the reserved strawberry rhubarb filling to create a soft pink, fruity frosting.
4. Assembling the Cake:
Place one cake layer on your serving plate. Spread a generous layer of the strawberry rhubarb filling over the top, followed by a layer of frosting. Repeat with the second cake layer and filling, then top with a final cake layer. Frost the top and sides with the remaining frosting. Decorate with leftover filling or fresh strawberries if you want.
5. Chilling and Serving:
Refrigerate the cake for at least 30 minutes so the layers set nicely. Serve chilled or bring to room temperature for a soft, melt-in-your-mouth texture. Enjoy your delicious, fruity Strawberry Rhubarb Layer Cake!
Can I Use Frozen Strawberries and Rhubarb?
Yes, frozen fruit works well—just thaw and drain any excess liquid before cooking the filling to avoid a watery texture.
How Should I Store Leftover Cake?
Store leftovers in an airtight container in the refrigerator for up to 3 days. Let slices come to room temperature before serving for the best flavor and texture.
Can I Make the Cake Ahead of Time?
Absolutely! Bake the cake layers and prepare the filling and frosting a day in advance. Assemble and frost the cake just before serving or chill assembled cake overnight for convenience.
What Can I Substitute for Buttermilk?
If you don’t have buttermilk, mix 1 cup of milk with 1 tablespoon lemon juice or white vinegar. Let it sit for 5 minutes before using—it’ll give the same tender texture to your cake.