This old fashioned Rhubarb Coconut Cake has a crunchy pecan & coconut topping. It’s the perfect dessert for spring!
Spring is rhubarb season, and this easy Rhubarb Coconut Cake is the perfect way to celebrate.
It’s a moist and tender cake, full of rhubarb, and topped with a coconut pecan crumble topping. Whipped cream on top is a must!
The recipe is from an Indiana women’s club cookbook from the 1980s. It makes a 13×9 inch pan, so there’s plenty to share. It would be a great ending to Easter dinner, or a dessert for a spring potluck (so would this Coconut Poke Cake!). I personally love it as a mid-afternoon treat with a cup of tea.
If you love rhubarb, don’t miss this easy Rhubarb Sauce recipe, Rhubarb Bars, Old Fashioned Rhubarb Crumble, and this list of 19 Rhubarb Desserts!
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When is rhubarb season?
Rhubarb is in season from late March until early June. You can find it in the produce department of your local grocery store, or at the farmer’s market.
Rhubarb’s bright red stalks resemble celery but they taste quite sour, which is exactly why a rhubarb cake or rhubarb muffins are the perfect use for it!
Cake ingredients
- You can typically find rhubarb in the produce section of your local grocery store or at the farmer’s market during the spring (it is most reliably available in May in the Midwest and Northeast). Look for bright red stalks!
- Butter, buttermilk, and an egg keep this cake tender and moist. See below or in the recipe notes for how to make your own buttermilk from vinegar and milk.
- A combination of white sugar and brown sugar add sweetness to the tangy rhubarb.
- All-purpose flour is the best choice for this cake-it’ll keep the rhubarb suspended in the cake beautifully.
Crumble topping ingredients
- A mixture of sugar, butter, and cinnamon create the crumbly streusel.
- Chopped pecans and coconut make it crunchy! You could substitute walnuts or almonds in place of the pecans, if you wish. I used sweetened coconut for this recipe, but unsweetened coconut would work well, too. If you’re a coconut fan, be sure to check out this Ugly Duckling Cake next!
How to make rhubarb Coconut cake
Start by combining the flour, salt, and baking soda in a medium bowl. Whisk to combine.
Then, cream the butter, white sugar, and brown sugar together with a hand mixer until light and fluffy.
Add the egg and vanilla, and mix to combine.
Add half of the buttermilk, then half of the flour mixture. Fold with a spatula to combine. Repeat with the remaining buttermilk and flour mixture, then fold in the chopped rhubarb. Don’t over mix the cake, which can make it tough.
Spread the batter into a greased 13×9 inch cake pan.
How to prepare the Coconut Pecan topping
Prepare the topping by placing the sugar in a large bowl. Cut the butter (cold from the refrigerator) into small cubes, and work the butter into the sugar with your fingers, a pastry blender, or a fork. You want to have clumps of butter about the size of peas.
Stir in the cinnamon, pecans, and coconut.
Sprinkle the topping evenly over the cake batter, then bake the cake for 45-50 minutes, or until a toothpick inserted into the center comes out clean.
Let the cake cool for at least 30 minutes before slicing it into squares. I got 15 squares out of this cake (3 squares from the short end and 5 squares from the long end).
Frequently Asked Questions
Store rhubarb cake in a covered container at room temperature for 3-4 days or in the refrigerator for 6-7 days.
To make homemade buttermilk, pour 1 tablespoon of vinegar into a glass measuring cup. Fill the cup the rest of the way with milk, up to the 1 cup line. That’s it! You just made your own buttermilk.
To freeze rhubarb cake, cover the cooked and cooled cake with plastic wrap, followed by a layer of aluminum foil. Freeze for up to one month. Alternatively, cut the cake into squares and wrap the individual squares in plastic wrap, then place them in a resealable freezer bag or freezer-safe container. The topping on the cake will not be as crunchy as a freshly baked cake, but it’ll still taste delicious.
To defrost, leave the cake at room temperature overnight or for at least eight hours.
Serving suggestions
This Rhubarb Cake already has a built-in pecan-coconut crumble topping, but in my opinion, the addition of whipped cream is a MUST!
The cool and creamy sweetness of the cream contrasts perfectly with the soft cake and crunchy topping. You can use either store-bought whipped cream/whipped topping, or make your own.
To make your own, combine 1 cup of heavy cream, 1 tablespoon of powdered sugar, and 1 teaspoon of vanilla in a stand mixer. Mix on high until soft peaks form (take care not to over mix it!). You can also use a hand mixer instead of a stand mixer.
Rhubarb Cake is best served the day that it’s made (the topping will be the crunchiest then!) but it’s still delicious several days later. Keep it on the countertop for 3-4 days or in the refrigerator for 5-7 days. Either way you store it, make sure to cover it with foil or a lid!
Want more rhubarb recipes? Check out 19 Delicious Rhubarb Desserts here, or try another rhubarb cake that I love: rhubarb upside down cake.
📖 Recipe
Rhubarb Coconut Cake
Ingredients
For the cake:
- ¾ cup brown sugar
- ½ cup granulated sugar
- ½ cup butter softened
- 1 egg
- 1 teaspoon vanilla
- 2 cups flour
- 1 teaspoon baking soda
- ½ teaspoon salt
- 1 cup buttermilk (see notes for a homemade version)
- 2 cups chopped rhubarb
For the topping:
- 3 tablespoons butter
- ½ cup sugar
- ¼ teaspoon cinnamon
- ½ cup shredded coconut
- ½ cup chopped pecans
- To serve: whipped cream or Cool Whip
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Instructions
- Preheat oven to 350°F. Grease a 13×9 inch baking pan with cooking spray.
- Place ¾ cup brown sugar, ½ cup granulated sugar, and ½ cup butter (softened) in a large bowl. Mix on high with a hand mixer until light and fluffy. Add 1 egg and 1 teaspoon vanilla, and mix to combine.
- In another large bowl, whisk together 2 cups flour, 1 teaspoon baking soda, and ½ teaspoon salt.
- Add half of the buttermilk to the butter/sugar mixture and mix to combine. Pour half of the flour mixture in, and stir with a spatula to combine. Repeat with the remaining buttermilk and flour mixture. Do not over mix the batter! Fold in 2 cups chopped rhubarb.
- Spread the mixture into the greased 13×9 inch pan.
- Cut the 3 tablespoons butter into small cubes. Place it in a medium bowl along with ½ cup sugar. Use your fingers to rub the butter into the sugar until the butter is in pea-size pieces. Stir in ¼ teaspoon cinnamon, ½ cup shredded coconut, and ½ cup chopped pecans. Scatter the mixture over the cake batter.
- Bake for 45-50 minutes, or until a toothpick comes out clean. Let cool and serve with whipped cream or Cool Whip.
I chose this recipe based on the photo alone. It looked light, tender, moist, flavorful. It delivered. I used chopped almonds instead of pecans. I used half and half with vinegar and a little water in place of buttermilk. And I added extra streusel topping, approximately 1.5x the amount called for, and I added a pinch of salt. I will tell you, I did NOT need the extra streusel topping. It was too much and I should have stuck with the recipe. I did like the tiny bit of added salt though. For picking a random rhubarb cake recipe off the internet, this was a surprise huge hit and I will be making it again. Thank you!
I’m so glad you enjoyed it! Thanks for taking the time to share your modifications. I, too, am always tempted to make more streusel. 🙂