This is the best Stone Fruit Crumble Bar recipe with oats to celebrate the final days of summer stone fruits. Using the last of the late season peaches, plums, and cherries we craft a delicious dessert bathed in a bit of brown butter and brown sugar. We create a version of a crispy recipe in bar form making these perfect for those end of summer parties.
Make these to serve for breakfast alongside your morning coffee or save them for a sweet afterschool snack or as part of a lovely brunch spread. We’ve got options here, folks. Scroll down to get the recipe card to make these today.

Ingredients for the Best Stone Fruit Crumble Bars
This stone fruit crumble bar recipe is mult-step but the ingredient list is simple:
- Unsalted butter: We’re using 8 tablespoons to brown for a savory crust that is balanced with sweetness from brown sugar. Brown butter is absolutely delicious in the crust portion of these bars. Nutty and rich—it’s a perfect bed to nestle your stone fruit filling.
- Brown sugar: This is used in both the crust and the filling.
- Stone Fruits: Seasonal stone fruits such as plums, peaches, and cherries are used here. Alternatively, you could use all plums or all peaches or even all cherries. You’ll look for a mix that will give you approximately 4 cups of diced fruit.
- Rolled Oats: Our crumble topping gets a lovely texture from organic old-fashioned rolled oats.
- Olive oil: The oat crumble here gets a helping hand with a mild blend of olive oil. I personally love the medium blend but the mild blend is a great option to bake with if you’re not wanting to use butter but also do not prefer a stronger flavor profile of the medium blend olive oil. In using the olive oil here for our oat crumble topping, we strike a balance with the richness of the brown butter so it’s not too heavy, not too sweet. It’s just right.

Preparing the Stone Fruit Crumble Bars
First, we’ll start by browning our butter for the crust. In a medium saucepan, melt 8 tablespoons unsalted butter (1 stick), over medium low heat. Turn the heat onto medium and begin stirring to move the butter around as it starts to melt. Once melted, the butter will begin to foam and sizzle around the edges. Keep stirring to prevent butter from burning. In about 5-8 minutes from when you started, the butter will turn golden brown. The foam will slightly subside and the milk solids on the bottom of the pan will toast and become golden. It will smell intensely buttery and nutty: the desired outcome. Remove from heat once you smell the butter, nutty scent. Allow to cool slightly as you prepare the rest of the crust.
Next, preheat your oven to 375 degree Fahrenheit. In a medium bowl, stir together your brown sugar, granulated sugar, salt, flour, and vanilla extract until well combined. Add in your brown butter and mix everything together well. Line a baking 9 x 13 baking dish with parchment paper and pour in your crust. Using a spatula, or your fingers, press the mixture into the bottom of your baking dish to form an even crust.
In a medium bowl, combine your fruits with lemon juice, lemon zest, chopped thyme leaves, brown sugar, and cornstarch. Stir together well until the cornstarch dissolves. Pour the fruit mixture onto your prepared crumble crust. Using a spatula spread the mixture evenly across the crust.
In a small bowl, mix together your oats, flour, brown sugar, salt, cinnamon and olive oil until well combined. Sprinkle the crumble topping over your fruit, using your fingers to spread the topping as evenly as possible.
Bake for 45-50 minutes in a 375 degree Fahrenheit oven until the fruit is bubbly and the oat topping is golden. Cool for at least 15 minutes before serving.


Frequently Asked Questions
- Can I use another oil besides olive? Yes! Coconut oil works beautifully here too.
- I don’t have lemon juice. What else could I use? Orange zest and orange juice are also great substitutes here.
- Would this crumble recipe work with other fruits? Absolutely! I love making seasonal variations of this for autumn using tart apples or berries for spring.

More Summertime Dessert Ideas
For more summertime dessert ideas check out the latest recipes:


The Best Stone Fruit Crumble Bars
Ingredients
Brown Butter Crust
- 8 tablespoons unsalted butter (1 stick) browned (see instructions)
- 1 teaspoon vanilla extract
- 1/2 cup brown sugar packed
- 1/4 cup granulated sugar
- 1/2 teaspoon kosher salt
- 1.5 cups all purpose flour
Stone Fruit Filling
- 1 cup cherries pitted and quartered
- 2 red plums pitted and diced into 1/2 inch chunks
- 2 yellow peaches pitted and diced into 1/2 inch chunks
- 1 donut peach pitted and diced into 1/2 inch chunks
- 1 tablespoon light brown sugar
- 1 teaspoon finely chopped fresh thyme leaves
- 1 tablespoon cornstarch
- Juice and zest of one lemon
Oat Crumble Topping
- 6 tablespoons olive oil
- 2 teaspoons light brown sugar
- 1/2 cup all purpose flour
- 1/2 cup rolled oats
- 1/2 teaspoon ground cinnamon
- Pinch kosher salt
Instructions
- In a medium saucepan, melt 8 tablespoons unsalted butter (1 stick), over medium low heat. Turn the heat onto medium and begin stirring to move the butter around as it starts to melt. Once melted, the butter will begin to foam and sizzle around the edges. Keep stirring to prevent butter from burning. In about 5-8 minutes from when you started, the butter will turn golden brown. The foam will slightly subside and the milk solids on the bottom of the pan will toast and become golden. It will smell intensely buttery and nutty: the desired outcome. Remove from heat once you smell the butter, nutty scent. Allow to cool slightly as you prepare the rest of the crust.
- Preheat your oven to 375 degree Fahrenheit. In a medium bowl, stir together your brown sugar, granulated sugar, salt, flour, and vanilla extract until well combined. Add in your brown butter and mix everything together well. Line a baking 9 x 13 baking dish with parchment paper and pour in your crust. Using a spatula, or your fingers, press the mixture into the bottom of your baking dish to form an even crust.
- In a medium bowl, combine your fruits with lemon juice, lemon zest, chopped thyme leaves, brown sugar, and cornstarch. Stir together well until the cornstarch dissolves. Pour the fruit mixture onto your prepared crumble crust. Using a spatula spread the mixture evenly across the crust.
- In a small bowl, mix together your oats, flour, brown sugar, salt, cinnamon and olive oil until well combined. Sprinkle the crumble topping over your fruit, using your fingers to spread the topping as evenly as possible.
- Bake for 45-50 minutes in a 375 degree Fahrenheit oven until the fruit is bubbly and the oat topping is golden. Cool for at least 15 minutes before serving.