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Slightly chewy and sweetly tart, these Rhubarb Oatmeal Bars combine a crunchy oat topping with flavorful rhubarb for a dessert the whole family will love.

Rhubarb Bars with Oatmeal
As spring reaches its peak, our family has enjoyed making our favorite rhubarb desserts, so I’ve been experimenting with some new rhubarb recipes. I simply can’t get enough fresh rhubarb whenever it is available.
When the tartness of rhubarb is combined with sweet, crunchy oatmeal topping, the result is sure to be a success. And these Rhubarb Oatmeal Bars? They’re a hit.

The thick and chewy oatmeal crust on these rhubarb bars provides a satisfying crunch, and allows you to pick up a bar without worrying about whether it will hold together.
Without being too tart or too sweet, the perfectly balanced flavor of the rhubarb filling gives a bright burst of flavor to every bite.
Whether they’re served as a snack out of hand, or as a warm dessert topped with a scoop of ice cream after dinner, Rhubarb Oatmeal Bars are a hit.

Rhubarb Bars with Oatmeal
You’ll need the following ingredients to make this recipe:
Filling Ingredients
- Rhubarb, sliced into ½-inch pieces
- Sugar
- Cornstarch
- Cinnamon
- Kosher salt
- Lemon juice

Crust Ingredients
- All-purpose flour
- Light brown sugar
- Old fashioned oats
- Butter, melted

Oatmeal Rhubarb Bars
Start by preheating the oven to 400°F. Grease a 9×13 pan with butter and set aside. In a large mixing bowl, combine the rhubarb, white sugar, cornstarch, cinnamon, and salt and stir to coat.
Add the lemon juice and stir again. Let the rhubarb mixture rest while preparing the crust.

While the rhubarb mixture rests, start preparing the topping by combining the flour, oats, and brown sugar in another bowl. Add the melted butter, and stir to combine.
Press half of the dry mixture into a buttered 9×13 pan. Next, pour the rhubarb mixture over the bottom crust. Finally, sprinkle the rest of the dry mixture on top.

Bake for 26-30 minutes; the crust should be golden brown. Let cool completely before slicing into bars.
Serve on their own or warmed and topped with ice cream.

Rhubarb Bar Recipes
Can’t get enough rhubarb recipes? These simple Rhubarb Bars with a shortbread crust and tangy rhubarb custard filling are a fun, easy spring dessert.
This Double Crumb Rhubarb Coffee Cake serves as the perfect excuse to eat cake for breakfast.
With only one bowl, this simple, old-fashioned Rhubarb Cake with Butter Sauce is a twist on classic Christmas desserts that’s great for all seasons.
Rhubarb Cookies get rave reviews every single time someone tries them. The rhubarb keeps them extra soft and gives a fun flavor twist to old-fashioned oatmeal cookies.

Rhubarb Oatmeal Bars
Ingredients
Rhubarb Filling Ingredients
- 2 pounds rhubarb sliced into ½-inch pieces, about 6 cups
- ⅔ cup sugar
- 3 tablespoons cornstarch
- ½ teaspoon cinnamon
- ½ teaspoon kosher salt
- 1 tablespoon lemon juice
Crust Ingredients
- 2 cups all-purpose flour
- 1 cup light brown sugar
- 1½ cups old fashioned oats
- 1 cup butter melted
Instructions
- Preheat oven to 400°F. Grease a 9×13 pan with butter and set aside. Combine the rhubarb with the white sugar, cornstarch, cinnamon, and salt in a large mixing bowl.
- Stir to coat the rhubarb and add the lemon juice. Stir again and the let the rhubarb rest while preparing the crust.
- In a separate mixing bowl, combine the flour, oats, and brown sugar. Add then melted butter. Stir to combine.
- Press half of this mixture into a buttered 9×13 pan. Pour the fruit over the bottom crust and then sprinkle the rest of the dry mixture on top.
- Bake for 26-30 minutes, until the crust turns golden brown. Let cool completely and slice into bars.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.















It’s in the oven now
I hope you love the bars as much as we do!
This absolutely filled my spring time rhubarb craving. I had about a cup of sweetened rhubarb sauce with vanilla left over so I spread it on the crust before adding the fillling. I don’t think the bar needed it but wow was it good!
I’m so glad you loved the bars!