Treat yourself to something truly special with this irresistible Rhubarb Cake with Butter Sauce. Tart, vibrant rhubarb is tucked into a moist vanilla butter cake and, once baked, is drenched with a silky, golden butter sauce that soaks right in. It’s the kind of nostalgic, old-fashioned dessert that makes you swoon at the first bite and almost always has friends and family asking for the recipe. Whether you’re using rhubarb fresh from the garden or the farmer’s market, get ready for a dessert that celebrates every ounce of its sweet-tart magic.

Ingredients You’ll Need

Rhubarb Cake with Butter Sauce Recipe - Recipe Image

Ingredients You’ll Need

The beauty of this recipe is how a few simple ingredients come together to create something spectacular. Each one plays its own important role—adding lift, structure, or that essential, buttery richness.

Rhubarb: Chopped into bite-sized pieces, rhubarb brings a tangy, fruity bite and beautiful pops of pink color.
Flour: The foundation of your cake, giving it lift and a soft, tender crumb.
Baking Powder: Don’t skip this! It helps the cake rise and stay fluffy.
Salt: Just a bit balances the sweetness and enhances all the flavors.
Sugar: Adds the necessary sweetness and also helps keep things moist.
Butter (Softened): Essential for a moist, flavorful cake and the star of the rich butter sauce.
Egg: Binds your batter and adds a touch of richness.
Vanilla: For that comforting, homey aroma and warmth in both cake and sauce.
Milk: Keeps the cake batter smooth and works with the butter to deliver a tender texture.
Heavy Cream (for the sauce): Turns the sauce ultra-creamy and velvety, making it dreamy when poured over cake.

How to Make Rhubarb Cake with Butter Sauce

Step 1: Prep Your Pan and Oven

Begin by preheating your oven to 350 degrees Fahrenheit. Take an 8 x 8-inch baking pan and give it a good spray with non-stick baking spray, making sure you get those corners. This will prevent any sticky mishaps when it’s time to serve. Set the prepared pan aside so you’re ready to go when the batter comes together.

Step 2: Cut and Measure Your Rhubarb

Chop the rhubarb into small, even pieces until you have two cups. The more evenly you cut the rhubarb, the more consistent every slice of cake will be—each bite packed with just the right amount of sweet-tart fruit.

Step 3: Mix the Dry Ingredients

Grab a medium mixing bowl and whisk together the flour, baking powder, and salt. This not only combines everything nicely but also aerates the flour, giving you a lighter cake. Set this mixture aside—your cake’s dry foundation is ready!

Step 4: Cream Butter and Sugar, Then Add Wet Ingredients

In a large bowl, cream together the softened butter and sugar until pale and fluffy. Take your time here—this is key to achieving a tender cake crumb. Beat in the egg and vanilla, then stir in the milk. You’ll end up with a lovely, silky mixture that smells like pure comfort.

Step 5: Combine Batters and Fold in Rhubarb

Slowly add the dry flour mixture to your wet ingredients, mixing until just combined. Avoid overbeating; a few lumps are fine. Gently fold in the chopped rhubarb, making sure it’s evenly distributed—this is what gives Rhubarb Cake with Butter Sauce its iconic jeweled look.

Step 6: Bake the Cake

Pour the batter into your prepared baking pan, smoothing the top with a spatula. Slide into the oven and bake for 45 to 50 minutes, until the cake is golden, a toothpick comes out mostly clean, and your kitchen smells heavenly. Let the cake cool slightly in the pan while you prepare the sauce.

Step 7: Prepare the Butter Sauce

While the cake bakes, get started on the butter sauce. In a saucepan, combine butter, heavy cream, sugar, and a splash of vanilla. Stir over medium heat until the sugar dissolves and the sauce is smooth, glossy, and fragrant. This magic potion is what makes Rhubarb Cake with Butter Sauce pure bliss.

How to Serve Rhubarb Cake with Butter Sauce

Garnishes

A drizzle of warm butter sauce is non-negotiable—pour it generously over each slice. For a fresh flourish, add a dollop of softly whipped cream, a scattering of fresh strawberries or raspberries, or even a tiny sprinkle of powdered sugar. If you have edible flowers or a few mint leaves, pop them on for an extra splash of color.

Side Dishes

This cake is lovely all on its own, but it truly shines alongside a scoop of vanilla ice cream or a spoonful of tangy crème fraîche. If you’re feeling adventurous, try pairing it with roasted rhubarb compote or a bright citrus salad for contrast.

Creative Ways to Present

Serve Rhubarb Cake with Butter Sauce in individual ramekins for a personalized touch at a dinner party. Or, cut the cake into cubes and skewer them along with fresh berries for a playful dessert platter. A slice packed in a lunchbox or picnic basket (with a little container of sauce on the side) brings unexpected delight on afternoon breaks.

Make Ahead and Storage

Storing Leftovers

Any leftover Rhubarb Cake with Butter Sauce should be cooled to room temperature, covered tightly, and kept in the refrigerator. It will stay fresh for up to 3 days. Be sure to store the cake and sauce separately; this keeps the texture perfect and lets you warm the sauce before serving.

Freezing

You can absolutely freeze this cake! Wrap individual slices or the whole cake (without sauce) tightly in plastic wrap, then foil, and pop them in the freezer for up to 2 months. Butter sauce can also be frozen in an airtight container—just thaw both in the fridge when you’re ready to indulge again.

Reheating

To reheat, gently warm the cake in the microwave or a low oven until just heated through. For the butter sauce, warm it slowly in a saucepan over low heat or blitz it in the microwave in 10-second bursts, whisking until smooth. Bring everything together again and enjoy that fresh-baked glow.

FAQs

Can I use frozen rhubarb instead of fresh?

Absolutely! Just measure the rhubarb straight from the freezer and fold it into the batter without thawing. If you thaw it first, drain off any excess moisture before adding so your cake doesn’t get soggy.

What if I don’t have heavy cream for the butter sauce?

No heavy cream? No problem. You can use whole milk or even half-and-half for the sauce, though the result will be a bit lighter but still deliciously rich.

Is Rhubarb Cake with Butter Sauce very sweet?

The cake has a lovely balance of sweet and tart thanks to the rhubarb, and the butter sauce adds extra richness and sweetness. If you prefer desserts on the less-sweet side, try reducing the sugar in the sauce just a little.

Can I make Rhubarb Cake with Butter Sauce gluten-free?

Yes! Substitute your favorite cup-for-cup gluten-free flour blend for the all-purpose flour. Just double check your baking powder to make sure it’s gluten-free as well.

What’s the best way to store extra butter sauce?

Keep leftover butter sauce in a jar or airtight container in the fridge for up to a week. A quick reheat brings it right back to life—try it over pancakes or waffles, too!

Final Thoughts

If you’re looking for a dessert that feels both classic and a little bit unexpected, give this Rhubarb Cake with Butter Sauce a try. It’s simple enough for a cozy family gathering, yet special enough to dazzle guests. Pour on that dreamy sauce and prepare for a chorus of happy sighs at the table!