These plum bars are layered with a soft buttery shortbread crust and spiced plum jam! This recipe uses simple ingredients and is easy to prepare. They are perfect to make during plum season!
If you love plums you are going to love these soft and gooey plum bars! The buttery shortbread is the same as my caramel bars and is the perfect base for homemade plum jam and shortbread crumbs.
This recipe requires minimum prep time, making it a simple recipe to throw together for any occasion. It's perfect to make at the end of summer and the beginning of Fall when plums are in season!
Why We Love These Plum Bars
- This is an easy recipe with simple ingredients and minimal prep time. They are just as easy to make as my Nutella bars!
- Each crumb bar has a shortbread crust with more shortbread crumbs on top. They are similar to a plum cobbler in bar form!
- Switch up the plum jam for your favorite fruit or serve it with a scoop of vanilla ice cream for a delicious dessert that everyone will love!
- They are perfect for any occasion- serve these plum bars for Thanksgiving or other holidays alongside my other fall dessert bars like my pecan brownies!
Ingredient Notes and Substitutions
Unsalted butter: This recipe is best with unsalted butter, but if you only have salted on hand leave out the ½ teaspoon of salt from the shortbread dough.
Flour: These plum bars have only been tested with all-purpose flour so I don't recommend substituting it!
Fresh plums: You can use any variety of plums; like red, black, or yellow. You can also switch out the fruit for strawberries, raspberries, or blueberries.
Chai spice: The chai spice elevates the jam with warm fall spices. You can make your own blend or buy a store-bought blend. You can substitute it with ground cardamom or cinnamon.
Find the full list of ingredients, measurements, and instructions in the recipe card below!
Before you start, line a square 8x8 baking pan with parchment paper and preheat the oven to 350 F/180 C.
Step 1: Make the jam. Cook the diced plums, brown sugar, granulated sugar, and chai spice over medium heat, stirring occasionally until the plums release all their juices. Use a masher to mash the plums, then continue cooking until the jam is thick (image 1 below).
Step 2: Cool the jam. Whisk in the cornstarch slurry, cooking until the jam is super thick and paste-like. Then transfer it to a small bowl and let it cool completely before using (image 2 below).
STEP 3: Combine the dry ingredients. In a stand mixing bowl or large bowl with a hand mixer, add the cold butter, all-purpose flour, brown sugar, granulated sugar, vanilla extract, and salt (image 3 above).
STEP 4: Mix the shortbread dough. Mix with the paddle attachment for 3-4 minutes until the butter is the size of small peas and the dough sticks together when squeezed in your hand (image 4 above).
STEP 5: Layer the shortbread. Reserve ½ cup of the shortbread crumb for the topping, then press the rest of it evenly into the prepared pan (image 5 below).
STEP 6: Layer the jam. Use an offset spatula to spread the cooled plum filling in an even layer on top of the shortbread dough layer (image 6 above).
STEP 7: Bake! Crumble the remaining shortbread pieces on top of the plum layer and bake! Let the plum bars cool completely on a wire rack.
When they are cool, chill the pan in the freezer for 15-20 minutes before removing them, and then cut them with a sharp knife. Dust with powdered sugar if desired and enjoy (image 7 above)!
Professional Baking Tips
- Use a kitchen scale. Baking with a scale is much more accurate than cup measurements. To convert this recipe, click the "metric" button next to the ingredients title on the recipe card. If you do not have a scale, use a spoon to fluff the flour first, then spoon it into your measuring cup.
- Let the plum jam cool. If you spread it on the shortbread while it's still warm, it will melt the butter in the shortbread.
- Make the jam REALLY thick. It should look very similar to a paste. If the jam is too thin, it will not set properly and will pool out when cut.
- Freeze them for clean cuts. For easy cutting, freeze the bars first for 15-20 minutes. Then use a sharp knife to cut them into bars.
I have not tested this recipe with store-bought jam. I am not sure it will be thick enough to hold up when cutting but would love to hear how they turn out if you try it!
Store leftover plum bars in an airtight container for 3-4 days at room temperature. You can also wrap the bars tightly with plastic wrap or store them in an airtight container for up to one month in the freezer.
more bar recipes to try
- 3 cups chopped red plums
- ¼ cup granulated sugar
- 2 tablespoon light brown sugar packed
- 1 ½ teaspoon chai spice
- 2 ½ tablespoon cornstarch
- ⅛ cup water
- Prepare a square 8x8 baking pan with parchment paper and set it aside.
- Add the plums, sugar, brown sugar, and chai spice to a pot. Cook over medium-high heat for 10-12 minutes or until they release all their juices. Use a masher to mash them. Continue cooking for another 8 minutes, or until the jam is thick.3 cups chopped red plums, ¼ cup granulated sugar, 2 tablespoon light brown sugar, 1 ½ teaspoon chai spice
- Whisk together the cornstarch and water and pour it into the pot.2 ½ tablespoon cornstarch, ⅛ cup water
- Cook for another 5 minutes, or until the jam is even thicker and paste-like.
- Transfer the jam into a small bowl and place it in the fridge to chill.
- When the jam is completely cool, make the shortbread.
- In a stand mixing bowl combine the butter, flour, sugar, brown sugar, and salt on low speed with the paddle attachment until the dough is crumbly and in pea sized pieces, this can take anywhere from 3-6 minutes.2 cups all-purpose flour, 1 cup unsalted butter, ⅓ cup granulated sugar, 2 tablespoon light brown sugar, ¾ teaspoon vanilla extract, ½ teaspoon kosher salt
- Preheat the oven to 350 F/180 C.
- Reserve ½ cup of the shortbread dough and set it aside.
- Evenly press the rest of the shortbread into the prepared baking pan.
- Evenly smear the cooled jam on top of the shortbread.
- Sprinkle the reserved shortbread crumbs on top of the jam.
- Bake for 33-38 minutes, or until the top of the shortbread is starting to turn golden brown.
- Let the bars cool completely on a wire rack.
- When cool, place the pan in the freezer for 15-20 minute to harden. Then remove them from the pan and use a sharp knife to cut them into clean bars. Dust with powdered sugar and enjoy!
- Store leftover plum bars in an airtight container for 3-4 days at room temperature or in the fridge.
The calorie information provided for the recipe is an estimate. The accuracy of the calories listed is not guaranteed.
This recipe was originally published in October 2021 and has been updated with new photos and content.