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This Rhubarb Coffee Cake is a delicious and easy-to-make recipe, perfect for springtime baking. The tart and tangy rhubarb is balanced by the sweetness of the cake and rich buttery crumb topping!

I grew up just a 3 mile bike ride down the gravel road from my grandparents. Therefore, my siblings and I were there quite frequently….stopping down on our bikes, dirt bikes, four-wheelers…you name it. Grandma always had delicious treats for us.
Most of the time her freezer was full of Buttermilk Cookies or Kolaches. But in the late spring when rhubarb was in season, she enjoyed making different recipes with her bountiful rhubarb plants.

When I made this coffee cake, I thought of her and wished I was still just a 3 mile drive away. Now a 3-hour car ride separates us, but I think of her all the time….especially when rhubarb is in season! Though her Rhubarb Muffins are always a hit and a long-time family fave, this Rhubarb Coffee Cake is sure to rival them!

Ingredients Needed
- All-Purpose Flour
- Brown Sugar – Light or dark brown sugar works great.
- Ground Cinnamon
- Butter – I use salted butter in this recipe. If you are using unsalted butter, simply add an additional 1/8 teaspoon salt to the batter.
- Baking Powder
- Baking Soda
- Salt
- Sugar
- Eggs – I always use the large size eggs
- Vanilla Extract
- Buttermilk – If you don’t have any buttermilk, you can make your own sour milk instead! (see notes in recipe card below)
- Rhubarb – You can use fresh rhubarb or frozen rhubarb (see notes below if using frozen rhubarb)

How to Make Rhubarb Coffee Cake
Streusel Topping
This topping is super simple to make. You’ll just add the flour, brown sugar, cinnamon and melted butter to a bowl and stir until combined. Then, refrigerate until the batter is ready. Giving it a chance to chill will help give you an extra crunchy, delicious topping.

Coffee Cake Batter
First, you’ll stir together the dry ingredients and set them aside.
Then, cream the softened butter and sugars in a large bowl with an electric mixer (or stand mixer) until light and fluffy. Then you’ll add the eggs and vanilla and mix until combined.

Next, you’ll add about half of the dry ingredients (don’t worry about getting it exact – just eyeball it!) and stir until just combined, followed by the buttermilk. Once the buttermilk is mixed in, add the rest of the flour mixture and stir just until combined.
Assemble the Cake & Bake
Scoop about half of the cake into the greased square pan and spread to an even layer.

Top with the diced rhubarb and about 1/2 cup of the streusel topping. Spoon the rest of the batter on top and gently spread. Don’t worry if it mixes with the streusel a bit – it all bakes together anyway! Lastly, top with the rest of the streusel and bake!



When baking the coffee cake, be sure to check it around 25 minutes. If it’s getting brown on top, but isn’t set in the center, I recommend covering with aluminum foil for the remainder of the bake. This will help the inside bake without it overbrowning. Once it’s done, let it cool on a wire rack.
Frequently Asked Questions
Absolutely. You’ll just want to be sure to defrost the rhubarb and drain the excess moisture (do NOT squeeze it, though!).
You can use either, but note that they’ll bake differently. I prefer to use a light metal pan (rather than the dark coated pans).
Let the coffee cake come to room temperature, then store in an airtight container.
Absolutely. If you plan to serve it more than two days out from the day you bake the coffee cake, simple wrap the cake well and freeze it.
It’s called coffee cake because traditionally, it’s meant to be enjoyed with a cup of coffee. I’m not a coffee drinker, so I’ll have a glass of milk on the side instead, haha!
I love eating a warm piece of coffee cake, as is! However, you could add a drizzle of powdered sugar icing or a scoop of vanilla ice cream and enjoy it for dessert!

Other Rhubarb Recipes I Love
Rhubarb Cookies
Rhubarb Custard Bars
Rhubarb Dump Cake

Rhubarb Coffee Cake
Equipment
- One 8×8 or 9×9-inch pan
Ingredients
Streusel Topping
- 1/2 cup flour
- 2/3 cup brown sugar
- 1 teaspoon cinnamon
- 1/4 cup butter melted
Coffee Cake Batter
- 1 3/4 cup flour
- 1 teaspoon baking powder
- 1/2 teaspoon baking soda
- 1/4 teaspoon salt
- 6 tablespoons butter softened
- 1/2 cup sugar
- 1/4 cup brown sugar
- 2 eggs
- 1 teaspoon vanilla
- 1/2 cup buttermilk*
- 1 1/2 cups diced rhubarb
Instructions
- Preheat oven to 350°F and grease or line an 8×8-inch or 9×9-inch square baking pan with parchment paper; set aside.
Make the Streusel Topping
- In a small bowl, combine the brown sugar, cinnamon and flour.
- Add the melted butter and stir until combined; refrigerate until ready to use.
Make the Batter
- Add the flour, baking powder, baking soda and salt to a bowl; stir and set aside.
- Add the butter and sugars to a large mixing bowl or a the bowl of a stand mixer.
- Cream the butter and sugars for a couple minutes, or until light and fluffy.
- Add the eggs and vanilla; stir well, scraping down the sides at least once.
- Add about half of the dry ingredients and mix to combine.
- Continue mixing while adding the buttermilk slowly; scrape the sides of the bowl.
- Add the remaining dry ingredients, stirring until just combined.
Assemble and Bake
- Pour a little more than half of the batter into the prepared pan; spread to an even layer.
- Sprinkle the rhubarb over the batter and then about 1/2 cup of the streusel topping.
- Spoon the remaining batter on and smooth it out to an even layer.
- Top with the streusel topping, pressing it into the batter gently.
- Bake for about 30 minutes, or until a toothpick inserted in the center comes out with just a few moist crumbs (not runny batter). If the top is browning but the cake isn't done in the center, top with aluminum foil and continue to bake. This will keep it from over-browning.
- Let cool, then cut and enjoy!
This cake was delicious and I made it exactly as the recipe was written. I loved that the rhubarb goes in a layer between the two layers of batter as opposed to the mixing it all in. The cake was spongy, moist and not overly sweet with just enough cinnamon in the topping to complement the rhubarb and not detract from the taste of it. The crunchy streusel topping is the bomb and i could eat that on everything, lol. Thanks for such a great recipe it and it will be my go to during rhubarb season.
Best Rhubarb Coffee cake ever!!!
I have made this several times this summer and it’s the BOMB.
I am gluten sensitive and I make this with my Namaste 1 to 1 Gluten Free Flour Blend. I do put about 3 cups of frozen rhubarb instead of 1.5 cups of fresh. I also add about a 1/4 cup of oats into the mix for the streusel topping. Because I am using GF flour it does take longer to bake, it usually takes about 45 minutes. But be sure to check with a toothpick for doneness. I like to have mine warm with cream over the top. Try it you’ll love it, people I have shared this with don’t know it’s gluten free.