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This sweet and tender Rhubarb Cake is speckled with plenty of tart, juicy rhubarb! Enjoy as is or serve with a warm vanilla butter sauce for a scrumptious dessert you’ll make again and again!
Why You Should Make Rhubarb Cake
- It’s EASY. It’s a snack cake that is so good as-is, it doesn’t need any frosting!
- Crunchy sugar topping. There’s a simple sprinkling of sugar on top that bakes into a light, crisp top layer, a perfect contract to the moist and tender cake!
- It’s super light and moist….good served alone or with the sauce!
- And the vanilla butter sauce! Though totally optional, I highly recommend giving this sauce a try sometime. It’s so good I’m pretty sure I could drink it! 🙂
- Once you’ve made some yummy rhubarb jam and a couple rhubarb pies, I love that this cake is an unexpected dessert everyone loves!
Wait…what is Rhubarb?!
Though technically a vegetable, rhubarb is a “culinary fruit,” meaning it’s typically prepared as a fruit in the kitchen. Rhubarb is a perennial and has long stalks with a large, dark green leaf on the end. The stalks look kind of like a reddish celery, but brings a tart, vibrant flavor, perfect for baking! It’s a popular commodity in the United Kingdom as well as in the midwestern states of the US (that’s me!) 😉
Ok, let’s get baking!
Ingredients Needed
- Butter – I prefer salted butter, but unsalted butter can also be used. Make sure the butter is at room temperature so it can easily be incorporated into the cake! You’ll need butter for the cake and the sauce
- White Sugar – Needed for the cake and for the sauce
- Egg – I always use large eggs when baking
- Vegetable Oil
- Vanilla Extract – For the cake and for the sauce
- All Purpose Flour
- Baking Powder
- Salt
- Buttermilk – Or you can make your own with milk and vinegar (more details below)
- Diced Rhubarb – I’ll walk you through how to prepare rhubarb below!
- Heavy Whipping Cream
How to Make Rhubarb Cake with Vanilla Butter Sauce
Make the Rhubarb Cake
Start by preparing the pan. You can either coat the pan in cooking spray or line the pan with parchment paper. Parchment paper makes for super easy removal from the pan!
Next, you’ll cream the butter and sugar. Then, add the wet ingredients (egg, vanilla and oil).
Then you’ll add half of the dry ingredients followed by the rhubarb and finally the remaining dry mixture.
Stir in the rhubarb until well-dispersed and spread it into the prepared pan.
Bake the cake for 40-45 minutes or until a toothpick pressed into the center of the cake comes out with just a few moist crumbs. Remove from the oven and let it cool on a wire rack.
Please note that different cake pans and different ovens can alter the cook time. I recommend always checking the cake at the earliest time listed and go from there! (You can always bake longer….but you can’t “unbake” if it’s overdone!)
Make the Butter Sauce
Making the sauce is simple! You’ll stir the heavy cream, sugar and butter together in a saucepan and bring it to a boil. Let it boil for 5 minutes then remove from the heat and stir in the vanilla. You can enjoy this warm or when it’s cooled to room temperature. It’ll thicken a bit in the fridge, so you might want to warm it up in the microwave if using later on!
Preparing Rhubarb for Baking
People often ask if rhubarb needs to be peeled before adding it to a recipe. I’ve never peeled a stalk of rhubarb in my life! Once you pick the stalk, you’ll want to cut both ends off (the leaf will be tossed as will the light colored part that was taken from the ground). Wash the rhubarb in cold water and pat dry. Cut into 1/2 inch pieces and add to the cake batter!
Make Your Own Buttermilk!
If you don’t have a carton of buttermilk in the fridge (I typically don’t!), making your own is easy. Add 1/2 tablespoon white vinegar into a liquid measuring cup. Add enough milk to make 1/2 cup total. Give it a stir and use in the cake!
How to Serve Rhubarb Cake
This cake is truly delicious on its own. It’s moist, delicate and has lots of juicy rhubarb throughout! However, if you want to take it up a notch, make the super simple vanilla rhubarb sauce!! It pairs beautifully with the cake. Add the sauce and/or a scoop of vanilla ice cream (or whipped topping!) and enjoy!!!
Frequently Asked Questions
Yes, with some stipulations. Make sure the frozen rhubarb is in small pieces. You don’t want huge chunks of rhubarb in the batter – it’ll create super wet pockets in the cake. The cake may take extra time in the oven to account for the frozen rhubarb.
Because the rhubarb brings lots of moisture to the cake, I recommend storing it in the fridge if you don’t plan to eat it all in the first day or two. It’ll keep in the fridge in an airtight container for up to 5 days.
Sure! I’d recommend using 2 cups of rhubarb and 1 cup strawberries. Cut the strawberries in small pieces (about the same size as your rhubarb pieces) and add them when you add the rhubarb!
Yes!! In fact, you’ll be SO glad you did! 🙂 Simply double the recipe and bake it as instructed. It’ll likely take an additional few minutes.
It can be either…and both are great! Red typically looks more pretty in dishes; green tends to have thicker stalks (see photos below). Use whichever you’ve got on hand! 🙂
Other Rhubarb Recipes You’ll Love
- Rhubarb Muffins
- Rhubarb Coffee Cake
- Frosted Rhubarb Cookies
- Rhubarb Custard Bars
- Easy Rhubarb Dump Cake
- Rhubarb Crunch
- Rhubarb Sauce
Rhubarb Cake
Equipment
- One 9×9-inch pan
Ingredients
Rhubarb Cake
- 1/4 cup butter softened
- 1 cup sugar
- 1 egg
- 1/3 cup vegetable oil
- 2 teaspoons vanilla extract
- 2 cups flour
- 2 teaspoons baking powder
- 1/2 teaspoon salt
- 1/2 cup buttermilk
- 3 cups diced rhubarb
- 1 tablespoon sugar
Vanilla Butter Sauce
- 1 cup heavy whipping cream
- 1/2 cup sugar
- 1/4 cup butter
- 1 teaspoon vanilla extract
Instructions
Rhubarb Cake
- Preheat oven to 350℉ and grease a 9×9-inch baking pan with cooking spray.
- In the bowl of a stand mixer (or in a large bowl with an electric mixer), cream the butter and sugar until light and fluffy.1/4 cup butter, 1 cup sugar
- Add the egg, oil and vanilla extract and stir to combine.1 egg, 1/3 cup vegetable oil, 2 teaspoons vanilla extract
- In a separate bowl, combine the flour, baking powder and salt.2 cups flour, 2 teaspoons baking powder, 1/2 teaspoon salt
- Stir half of the dry ingredients into the batter until combined.
- Add the buttermilk and finish with the remaining dry ingredients, stirring just until combined.1/2 cup buttermilk
- Gently mix in the rhubarb.3 cups diced rhubarb
- Spread into pan, sprinkle with sugar and bake 40-45 min.1 tablespoon sugar
Vanilla Butter Sauce
- In a small saucepan, combine the heavy whipping cream, sugar and butter.1 cup heavy whipping cream, 1/2 cup sugar, 1/4 cup butter
- Bring to a boil; let it boil gently over medium heat for 5 minutes.
- Remove from the heat and stir in the vanilla.1 teaspoon vanilla extract
- Serve with the cake.
