Rhubarb Cake with Rhubarb Sauce is a deliciously moist, tender cake loaded with diced rhubarb and topped with rhubarb sauce. It is one of my favorite ways to use up all of that rhubarb that grows in abundance here. And no, I am not complaining, I love it! When everything is coming up rhubarb, try my Rhubarb Bars, too!

Piece of Rhubarb Cake With Rhubarb Sauce on it topped with vanilla ice cream.
Want to save this recipe?
Just enter your email and get it sent to your inbox! Plus you’ll get new recipes from us every week!

Ingredients & Substitutions

  • Rhubarb: It’s all about the rhubarb in this recipe. You will need a total of 6 cups of diced rhubarb in this recipe (about 2 pounds). Three cups are used in the cake (which is one of my favorite cakes just on its own) and 3 more cups for the sauce. So, round up your rhubarb and get this cake made! Frozen rhubarb would also work; just let it thaw and drain before using.
  • Sugar: Only light brown sugar is used in the cake. (Granulated sugar is needed for the sauce.) The brown sugar adds sweetness and moisture.
  • Vegetable Oil: Vegetable oil helps keep the cake moist, even when it’s stored in the refrigerator. It also adds some fat to the cake batter.
  • Buttermilk: The tanginess of the buttermilk complements the tartness of the rhubarb. It also reacts with the baking soda to help the cake rise. If you don’t have any on hand, make homemade buttermilk to use!
  • Rhubarb Sauce: The rhubarb sauce adds a lot more rhubarb flavor to the cake, and it is easy to make with just three ingredients.
Rhubarb Cake With Rhubarb Sauce in a white pan on a wooden table and partly cut into pieces from overhead.

Can I Make The Cake and Sauce Ahead Of Time?

Sure! You can make both ahead of time. The cake can be baked a day in advance and the sauce can be made several days in advance and stored in the refrigerator. Add the sauce when ready to cut and serve.

More Ways To Use Rhubarb Sauce

The rhubarb sauce is delicious on this rhubarb cake, yes, but don’t stop there! Here are more delicious ways to use the sauce:

  • Drizzle rhubarb sauce over pancakes and waffles.
  • Pour warm rhubarb sauce over a bowl of no-churn ice cream. Top with whipped cream and nuts for a yummy sundae!
  • Layer rhubarb sauce with Greek yogurt and granola for a healthy and flavorful parfait.
  • Spread rhubarb sauce over a plain or vanilla cheesecake for an extra flavor.
  • Stir rhubarb sauce into your morning oatmeal for added sweetness and a touch of tartness.
  • Use rhubarb sauce to fill pastries, such as turnovers, danishes, or hand pies.
  • Spread rhubarb sauce on toast, scones, or biscuits (instead of jam).
Piece of Rhubarb Cake on a white plate on a wooden table.

How To Store Rhubarb Cake With Rhubarb Sauce

If the sauce has been added to the cake, store the cake in the refrigerator, covered. If left at room temperature, it could spoil. It will last up to a week. If storing the cake and sauce separately, the cake can be stored at room temperature for up to 3 days. The sauce should be stored in an airtight container in the refrigerator for up to a week.

Fork taking a bite out of a piece of Rhubarb Cake With Rhubarb Sauce on a white plate.

Freezing Rhubarb Cake

This cake freezes well, but freeze it without the rhubarb sauce. (You can always add that later, when ready to serve.) To freeze the cake, double-wrap it in plastic wrap and store it in a freezer-safe container for up to three months. Be sure to label and date the container. Thaw the cake in the refrigerator before serving.

Whole Rhubarb Cake on a wooden table with Rhubarb Sauce off to the side from overhead.

Rhubarb Cake With Rhubarb Sauce

Prep Time 15 minutes
Cook Time 45 minutes
Total Time 1 hour
Rhubarb Cake with Rhubarb Sauce is a deliciously moist cake loaded with diced rhubarb and topped with rhubarb sauce. It is one of my favorite ways to use up all of that rhubarb that grows in abundance here!



  • 1 ½ cups (300 g) light brown sugar, packed
  • cup (145 g) vegetable oil
  • 2 large eggs, room temperature
  • 1 cup buttermilk
  • 1 teaspoon kosher salt
  • 1 teaspoon baking soda
  • 1 teaspoon vanilla extract
  • 2 ½ cups (312.5 g) all-purpose flour
  • 1 pound rhubarb, diced (about 3 cups)

Rhubarb Sauce

  • 1 pound rhubarb, cut into ½-inch pieces (about 3 cups)
  • ¼ cup water
  • cup (67 g) granulated sugar



  • Preheat oven to 350°F. Spray a 9×13-inch baking dish with nonstick cooking spray.
  • To a large mixing bowl, add brown sugar, vegetable oil, eggs, buttermilk, salt, baking soda, and vanilla. Whisk to combine.
  • Stir in the flour and mix until just combined.
  • Fold in diced rhubarb. Pour the batter into the prepared baking dish.
  • Bake for 45-50 minutes, or until an inserted toothpick comes out with a few crumbs, but no wet batter.
  • Remove the cake from the oven and let it cool while you prepare the rhubarb sauce.

Rhubarb Sauce

  • To a medium saucepan over medium-high heat, add rhubarb, water, and sugar. Bring to a boil. Continue to cook until the rhubarb starts to break down (about 10-15 minutes).
  • Remove from heat and allow the mixture to cool slightly before pouring over the cake.

Did you make this recipe?

Thank you for making my recipe! You took pictures, right? Well go ahead and post them on Instagram! Be sure to mention me @iambaker and use the hashtag #YouAreBaker.

What the Test Kitchen had to say about this recipe:


This cake with rhubarb sauce is a wonderful blend of sweet and tart. The cake is moist and flavorful, while the rhubarb sauce adds a lovely tangy contrast. Perfect for a summer dessert.


I loved this cake so much without the sauce, so I was curious if the sauce would add to or take away from the cake itself. Well, it works! And, I want to use the sauce for my toast, too!


The rhubarb adds a unique tartness that complements the sweetness of the cake beautifully. It's a perfect dessert for those who enjoy a mix of sweet and sour flavors.


The cake itself is soft and rich, and the rhubarb sauce adds a bright, fruity note that cuts through the sweetness. A delightful dessert that's perfect for any occasion.


The combination of this moist cake with the tangy rhubarb sauce is simply divine. The flavors are well-balanced, and the rhubarb sauce adds a refreshing zing. A must-try for rhubarb lovers!

Share with your friends!

Categorized in: ,

Related Recipes

Meet Elizabeth Keeney

Leave a Reply

Your email address will not be published. Required fields are marked *

Recipe Rating

This site uses Akismet to reduce spam. Learn how your comment data is processed.