These Rhubarb Oatmeal Bars are a perfect balance of tangy and sweet, featuring a crumbly oat crust paired with a luscious rhubarb filling. I love making these in spring when rhubarb is at its peak, and even friends who usually shy away from rhubarb end up asking for seconds. They’re great as a snack or a light dessert, and the oat topping adds a wonderful texture that complements the tartness of the fruit.
Ingredients
For the crust and topping:
1 1/2 cups all-purpose flour
1 1/2 cups rolled oats
1 cup packed brown sugar
1/2 teaspoon baking soda
1/2 teaspoon salt
3/4 cup unsalted butter, melted
For the rhubarb filling:
1/4 cup granulated sugar
2 teaspoons cornstarch
4 cups chopped fresh rhubarb
1 teaspoon vanilla extract
(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)
Directions
Preheat the oven to 350°F (175°C) and grease a 9×13-inch baking dish.
In a large bowl, combine the flour, oats, brown sugar, baking soda, and salt.
Stir in the melted butter until the mixture becomes crumbly.
Press half of this oat mixture firmly into the bottom of the prepared baking dish to form the crust.
In a separate bowl, mix the granulated sugar and cornstarch. Add the chopped rhubarb and vanilla extract, tossing gently to coat the rhubarb evenly.
Spread the rhubarb filling over the crust layer.
Crumble the remaining oat mixture evenly over the rhubarb layer.
Bake for 35-40 minutes until the top is golden brown and the filling is bubbly.
Let the bars cool completely on a wire rack before cutting to ensure they hold together well.
Servings and timing
This recipe makes about 24 bars, perfect for sharing or storing for later. Prep time takes around 15 minutes, and baking takes 35-40 minutes, so the total time is just under an hour.
Variations
I like to experiment with this recipe by swapping the rhubarb for other fruits like strawberries, raspberries, or a mixed berry blend. Adding a teaspoon of cinnamon or nutmeg to the oat mixture also adds a warm, cozy flavor. For a gluten-free option, I substitute the all-purpose flour with a gluten-free blend. If I want extra crunch, I sometimes sprinkle chopped nuts like walnuts or pecans on top before baking.
Storage/Reheating
I store these bars in an airtight container at room temperature for up to 3 days. For longer storage, they keep well in the fridge for up to a week. I’ve also frozen them successfully—just wrap individually and freeze for up to 3 months. To reheat, I warm them gently in the oven at 300°F for about 10 minutes or until heated through, which brings back their fresh-baked texture.
FAQs
Can I use frozen rhubarb instead of fresh?
Yes, frozen rhubarb works well. Just thaw and drain any excess liquid before using to prevent the bars from becoming soggy.
How do I know when the bars are done baking?
The top should be golden brown, and you should see the filling bubbling through the oat topping. If the edges start to pull away slightly from the pan, that’s a good sign too.
Can I make these bars ahead of time?
Absolutely. I often prepare them a day ahead and let them sit overnight. The flavors actually meld together nicely after resting.
Can I substitute butter with a non-dairy alternative?
Yes, melted coconut oil or vegan butter can be used as a substitute for the butter, though the flavor will be slightly different but still delicious.
How do I keep the bars from falling apart when cutting?
Allowing the bars to cool completely before cutting helps them set firmly. Using a sharp knife and wiping it clean between cuts also makes slicing easier.
Conclusion
I find these Rhubarb Oatmeal Bars to be a delightful treat that combines the best of sweet and tangy flavors with a satisfying oat crunch. They’re easy to make, versatile, and perfect for sharing with family and friends. Whether I enjoy them fresh from the oven or as a snack later in the day, they never disappoint. Give them a try and see how delicious rhubarb can be!
Recipe:
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Rhubarb Oatmeal Bars
- Total Time: 50-55 minutes
- Yield: About 24 bars
- Diet: Vegetarian
Description
These Rhubarb Oatmeal Bars feature a tangy rhubarb filling with a crumbly oat crust and topping, offering a perfect balance of sweet and tart flavors in an easy-to-make snack or dessert.
Ingredients
1 1/2 cups all-purpose flour
1 1/2 cups rolled oats
1 cup packed brown sugar
1/2 teaspoon baking soda
1/2 teaspoon salt
3/4 cup unsalted butter, melted
1/4 cup granulated sugar
2 teaspoons cornstarch
4 cups chopped fresh rhubarb
1 teaspoon vanilla extract
Instructions
- Preheat the oven to 350°F (175°C) and grease a 9×13-inch baking dish.
- In a large bowl, combine the flour, oats, brown sugar, baking soda, and salt.
- Stir in the melted butter until the mixture becomes crumbly.
- Press half of this oat mixture firmly into the bottom of the prepared baking dish to form the crust.
- In a separate bowl, mix the granulated sugar and cornstarch. Add the chopped rhubarb and vanilla extract, tossing gently to coat evenly.
- Spread the rhubarb filling over the crust layer.
- Crumble the remaining oat mixture evenly over the rhubarb layer.
- Bake for 35-40 minutes until the top is golden brown and the filling is bubbly.
- Let the bars cool completely on a wire rack before cutting to ensure they hold together well.
Notes
Frozen rhubarb can be used; thaw and drain excess liquid before use.
To keep bars from falling apart, allow cooling completely before cutting and use a sharp knife.
Substitute butter with melted coconut oil or vegan butter for a dairy-free option.
Try adding cinnamon or nutmeg to the oat mixture for extra flavor.
For gluten-free, replace all-purpose flour with a gluten-free flour blend.
Store bars in an airtight container at room temperature for up to 3 days, or refrigerate up to a week. Freeze up to 3 months.
Reheat gently in a 300°F oven for about 10 minutes to restore texture.
- Prep Time: 15 minutes
- Cook Time: 35-40 minutes
- Category: Snack, Dessert
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 bar
- Calories: 180
- Sugar: 12g
- Sodium: 110mg
- Fat: 7g
- Saturated Fat: 4g
- Unsaturated Fat: 3g
- Trans Fat: 0g
- Carbohydrates: 27g
- Fiber: 2g
- Protein: 2g
- Cholesterol: 20mg
