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Old-fashioned Rhubarb Crunch begins with a brown sugar oatmeal crumble layer that is topped with fresh rhubarb and then it is finished with a second layer of crumble over the top.
The Strawberry Rhubarb Fruit Crisp is an ever-popular dessert in the summertime and this crunch variation takes it to an even tastier new level.
I hope you’re enjoying as beautiful of a spring as we are! I’m so happy to be deep into rhubarb season and I’m looking forward to more fruit desserts through the summer as well.
I’m excited to be working on more rhubarb recipes again this year. We have so many to share and I’m working through a list of them for you!
So far, I’ve shared a Rhubarb Crisp, Rhubarb Cake with Butter Sauce, Rhubarb Bars, Old Fashioned Rhubarb Pie and the Double Crumb Rhubarb Coffee Cake.
This No Churn Rhubarb Ice Cream from Our Table for Seven and this Strawberry Rhubarb Galette from 365 Days of Baking are also on my list to try soon.
What is a Rhubarb Crunch?
A fruit crunch is similar to fruit crisps, but it has an oatmeal crumble layer on the bottom as well as a top.
Similar to a bar, but still gooey enough to eat with a spoon. It’s perfect with a scoop of vanilla ice cream or a dollop of freshly whipped cream.
A generous amount of brown sugar in the crumb layers and plenty of white sugar for the filling nicely balances the tartness of the rhubarb.
How to Make Rhubarb Crunch?
First you’ll start by making a brown sugar oatmeal crumb layer. Melt some butter and add oatmeal, flour and brown sugar. Mix until crumbly.
Press half of these crumbs on the bottom of the pan. Then top with some chopped rhubarb. You can use fresh or frozen.
If you choose to use frozen rhubarb, you’ll want to check out the section below on how to use frozen rhubarb in this rhubarb crunch recipe.
The next step of the recipe is what makes the rhubarb crunch unique. You boil a mixture of water, sugar and cornstarch until thickened and bubbly.
Then pour the mixture over the rhubarb in the pan. Top with the remaining half of the oatmeal crumb mixture and bake for about an hour.
Like most fruit crisps, I think a crunch is best served warm with ice cream or whipped cream, but the leftovers are also delicious the next day, eaten cold straight from the refrigerator.
How to use frozen rhubarb in this recipe?
You can make this recipe using fresh or frozen rhubarb.
If you choose to use frozen rhubarb thaw the rhubarb first and let any excess liquid drain off. Don’t squeeze any liquid out, just drain what naturally thaws out of the rhubarb.
You’ll want to plan ahead to use frozen rhubarb. Depending on the temperature of the room, it takes 4-6 hours to thaw a quart of rhubarb completely.
So you may want to take it out of the freezer the night before. When in a pinch, I’ve also used the auto defrost feature on the microwave to give it a head start, just be careful not to heat it too high and cook it.
Rhubarb Crunch Recipe
- Preheat oven to 350° F. In a medium bowl, combine the flour, oatmeal, brown sugar, melted butter and cinnamon until crumbly. Press 1/2 of the crumb mixture into a greased 9 x 9 inch or 11 x 7 inch baking pan.
- Spread the diced rhubarb in the pan. In a small saucepan, combine the white sugar, water and cornstarch. Bring to a boil over low heat. Continue to cook and stir until the mixture is thick and clear. Pour the sugar mixture over the rhubarb in the baking pan. Top with the remaining crumb mixture.
- Bake for 1 hour. Cool at least slightly before serving. To serve, cut into squares and top with ice cream or whipped cream. Best served warm.
Looking for more rhubarb recipes? Full of tender apples, beautifully citrusy rhubarb, and crowned with a classic brown sugar oat crisp topping, Apple Rhubarb Crisp blends seasons together in sweet tart harmony. It’s different and it’s delightful!
Rhubarb Crunch
Ingredients
- 1 cup all purpose flour
- 3/4 cup quick cooking oatmeal
- 1 cup brown sugar
- 1/2 cup melted butter
- 1 teaspoon cinnamon
- 4 cups diced rhubarb
- 1 cup white sugar
- 1 cup water
- 2 tablespoons cornstarch
- Vanilla ice cream or whipped cream for serving
Instructions
- Preheat oven to 350° F. In a medium bowl, combine the flour, oatmeal, brown sugar, melted butter and cinnamon until crumbly. Press 1/2 of the crumb mixture into a greased 9 x 9 inch or 11 x 7 inch baking pan.
- Spread the diced rhubarb in the pan. In a small saucepan, combine the white sugar, water and cornstarch. Bring to a boil over low heat. Continue to cook and stir until the mixture is thick and clear. Pour over the rhubarb in the baking pan. Top with the remaining 1/2 of the crumb mixture.
- Bake for 1 hour. Cool at least slightly before serving. To serve, cut into squares and top with ice cream or whipped cream. Best served warm.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
{originally published 4/11/19 – recipe notes and photos updated 5/25/21}
I made this for a group that I cook for every Wednesday. They devoured it! Served it warm with strawberry whipped cream. Also added strawberries to the Rhubarb when I cooked it down. Will make this again!!!
That sounds awesome, Donna. I’m glad it was a hit!
I’ve grown up eating this and now it’s the first thing I make every rhubarb season. I add vanilla to the syrup after it thickens, and I sprinkle a little strawberry Jello over the rhubarb before pouring the syrup. It helps keep the dish from becoming too runny, and adds a tiny bit of sweetness to the rhubarb filling.
I’ve never tried adding jello to the filling, Sharon. I’m thrilled you’re enjoying the recipe.
We loved this. The rhubarb looks deliciously red in this recipe, perhaps due to the sugar and water mixture. The presentation is pretty and the dessert is easy to cut and serve. Keeps and tastes great the next day. I did only use 3/4 cup white sugar and it was still very sweet. Topped with ice cream.
I’m glad it was a hit, Judy.
My very picky husband loves this! Thanks for such a great recipe!
I’m so happy to hear it, Connie.
My mom has been making this exact recipe for at least 40 years. It is now down to me to make it for her. It is absolutely delicious!
I’m thrilled your family likes it too, Kim.
Everyone that tried this loved it. My grandkids usually don’t eat rhubarb but this was a big hint. I doubled the crust absolutely a hit. Made it 3 times in a week.
Tried with fresh blueberries first, made a second time with raspberries and strawberries it’s a hit with the kids and adults here! We are making this once a week and will continue once our wild berries bare fruit this summer and fall! Thank you for the recipe!
You’re welcome, Sheila. I’m glad you’ve found ways to make the rhubarb crunch your own. Enjoy!
Can I use apples instead of rhubarbs?
Hi, Anne! That should work just fine.
I got this recipe from my husbands auntie. There isn’t A better recipe!! I’ve tweaked it by putting strawberries in it or raspberries. You can also use the same crust and topping recipe and change fruit to apple, peach or pears. Core, peel, and slice thin. Always a hit at get togethers!
Glad to hear that you’ve been loving the rhubarb crunch, Rayanna. Happy cooking!
I had a couple “ Diamond Pecan Ready Made Crust”. I made the recipe as listed and used the pre made crust as the bottom . It was phenomenal. I was able to make two pies. Keeping this recipe.
I’m so glad you loved the recipe, Sharon, and that you were able to make the pre made crust work well with the dish. Enjoy the pies, and happy baking!