These Strawberry Rhubarb Oat Bars are filled with chunks of fresh strawberries and rhubarb and topped with a buttery oatmeal crumble.

Strawberry rhubarb oat bar squares with a bowl of fresh strawberries

I have so many recipes for baked bars on the blog because they’re usually really simple to make and perfect to snack on! Some of my favorites are these Caramel Butter Cake Bars or if you prefer really simple and no fuss, my Apple Pie Bars are what you should be making this week! But let’s focus on this latest recipe, Strawberry and rhubarb is a traditional combination because the sweet strawberries balance out those chunks of super tart rhubarb. Rhubarb is definitely seasonal and I know a lot of people who aren’t keen on it, but paired with something else or in a pie, rhubarb is the perfect summer dessert. I remember my dad used to grow it in the garden when I was a kid and my mom would cut it into raw strips and let me dip them in sugar. By itself it’s very sour so that’s probably why the sugar was added.

Ingredients needed for strawberry rhubarb oat bars

  • Flour, all purpose is perfect.
  • Powdered sugar.
  • Butter, unsalted.
  • Fresh strawberries, rinsed and patted dry with a paper towel.
  • Fresh rhubarb, find it in the produce section of your grocery store. For some reason it’s never a very big display so you might have to ask.
  • Granulated sugar.
  • Cornstarch, this will help the fruit thicken up as it bakes.
  • Vanilla extract.
close up picture of strawberry rhubarb oat bars

how to make strawberry rhubarb oat bars

Making The Shortbread Style Base

  1. Mixing the dough

    Combine the flour, powdered sugar and butter until a dough forms.

  2. Getting the dough into the pan

    Transfer the dough to your prepared baking pan and using your fingers and palm of your hand, press the dough out towards the edges of the pan until the bottom of the pan is evenly covered.

  3. Baking the base

    Bake in the oven and prepare the filling as the base is baking.

  4. Preparing the filling

    Strawberries and rhubarb will release some liquid when cooked but we want to leave that out of the recipe or the oat bars will be a soggy mess. Once the fruit has been sweetened with sugar and simmered for a short time, you’ll use a slotted spoon to scoop it into the base, eating behind the liquid in the pan.

  5. Making the crumble topping

    This is a mixture of flour, brown sugar and butter and combined together. The mixture gets sprinkled over the fruit and baked until golden brown.

FAQ’s about rhubarb

Is rhubarb healthy?

High in antioxidants and fiber, rhubarb is good for you in moderation.

I heard rhubarb can be poisonous, is that true?

The rhubarb stalks are fine to eat but the large green leaves of the plant are toxic and should be avoided, yikes!

How do you grow rhubarb?

Rhubarb is grown from a seed and then it will bloom into something that resembles a large bush. It’s only in season for a few months of the year and can be hard to find in the regular grocery stores.

Can I freeze rhubarb?

Definitely! You can even add it to smoothies or frozen drinks in the summer.

Do you need to peel rhubarb?

No you don’t need to peel your rhubarb. A good rinse under the tap is recommended though.

More tasty bar recipes

Strawberry Rhubarb Oat Bars

Course: Dessert
Cuisine: American
Prep Time: 30 minutes
Cook Time: 1 hour 15 minutes
Total Time: 1 hour 45 minutes
Servings: 24
Author: foodnessgracious
Delicious and buttery these strawberry rhubarb oat bars are a great way to kick of your summer baking! Easy to make and so tasty, they're perfect for a quick snack or picnic potluck!
Print Recipe


For The Base

  • 2 cups all purpose flour
  • 1/2 cup powdered sugar
  • 8 ounces butter, at room temperature

For The Filling

  • 4 cups sliced strawberries
  • 3 cups sliced rhubarb
  • 1/2 cup sugar
  • 3 tbsp cornstarch
  • 2 tsp vanilla extract

For The Topping

  • 1 cup brown sugar
  • 3/4 cup all purpose flour
  • 3/4 cup rolled oats
  • 1 tsp cinnamon
  • 1/2 cup butter


  • Preheat the oven to 350 degrees F and line a 9×13 inch baking pan with parchment paper.
  • In the bowl of a stand mixer, combine the flour , powdered sugar and softened butter.
  • Mix on low speed until a dough forms.
  • Transfer the dough to the prepared pan and press it down towards the edges of the pan until all of the pan has been covered evenly with dough.
  • Place the base into the oven and bake for 20 minutes.
  • While the base is baking, prepare the filling.
  • Add the sliced strawberries and rhubarb to a large pan over a medium heat.
  • Add the sugar, vanilla and cornstarch and gently mix through the fruit.
  • Cook for 2-3 minutes until the sugar and cornstarch dissolve then turn off the heat.
  • When the base is ready take it out of the oven and using a slotted spoon, transfer the fruit to the base leaving behind the liquid.
  • Spread the fruit out evenly.
  • In another bowl, combine the ingredients for the topping except the butter and mix well.
  • Grate the butter into the mixture then rub the butter with your fingertips into evenly sized pebbles of butter.
  • Sprinkle the topping over the fruit and place back into the oven.
  • Bake for 55 minutes and the crumb topping is golden.
  • Let the bars cool before slicing into squares.