Rhubarb Shortbread Bars
There’s something nostalgic and grounding about the first Rhubarb Shortbread Bars harvest of the year. Where I live, it usually pokes out from the garden soil just as the last chill of winter gives way to spring. That’s when I know it’s time to pull out my shortbread bar pan.
The inspiration for this recipe actually came from a mishap—years ago, I was trying to recreate my grandmother’s rhubarb pie for a brunch. I ran out of pie crust ingredients and had to improvise with a buttery shortbread base. It turned out better than I ever imagined. The crisp base with that tart-sweet rhubarb filling was so satisfying that people started asking for “those rhubarb squares” every spring.
This recipe has gone through a dozen tweaks since then, and I can finally say with confidence: this is the one. Balanced in texture, rich in flavor, and reliably easy every time I bake it.
Why You’ll Love These Rhubarb Shortbread Bars
The sharp tang of rhubarb plays beautifully against the soft sweetness of the crust.
The shortbread layer is rich, buttery, and never crumbly in the wrong way.
It’s easy enough for a weeknight bake, impressive enough for guests.
These bars hold their shape well, which makes them perfect for packing up for potlucks or picnics.
It’s a brilliant way to showcase rhubarb when it’s in season—and a reason to stock up and freeze some for later.
The recipe is customizable, forgiving, and always a crowd-pleaser.
Ingredients for Rhubarb Shortbread Bars
Shortbread Crust
1 cup (226g) unsalted butter, softened
½ cup (100g) granulated sugar
2 cups (240g) all-purpose flour
¼ teaspoon salt
Rhubarb Filling
3 cups (375g) fresh rhubarb, chopped into small pieces
1 cup (200g) granulated sugar
2 large eggs
¼ cup (30g) all-purpose flour
½ teaspoon vanilla extract
¼ teaspoon salt
Ingredient Notes:
Use unsalted butter to balance the added salt yourself.
If using frozen rhubarb (which I often do when the craving hits out of season), thaw completely and drain off the excess liquid.
The smaller the rhubarb pieces, the more evenly they bake—especially in the middle of the pan.
Equipment You’ll Need
9×13 inch baking pan
Two mixing bowls
Whisk or electric hand mixer
Measuring cups and spoons
Rubber spatula or wooden spoon
Cooling rack
How to Make Rhubarb Shortbread Bars (Step-by-Step)
1. Preheat and Prepare
Set your oven to 350°F (175°C). Lightly grease a 9×13-inch pan or line it with parchment paper. I always go with parchment—makes removing and slicing the bars a breeze.
2. Make the Shortbread Crust
In a mixing bowl, cream together the softened butter and sugar until light and fluffy. Add in the flour and salt and stir until the mixture looks crumbly but holds together when pressed. Press the dough evenly into the prepared pan. Bake for about 15 minutes or until the edges just begin to brown. Let it cool slightly while you make the filling.
3. Mix the Rhubarb Filling
Whisk together the sugar, eggs, flour, vanilla, and salt until smooth. Then fold in the rhubarb. The mixture will look rustic and slightly bubbly—that’s perfect.
4. Pour and Bake
Pour the rhubarb mixture over the warm crust and spread it out evenly. Return the pan to the oven and bake for another 40–45 minutes. The filling should be just set and starting to turn golden on top.
5. Cool and Slice
Let the bars cool completely in the pan. Don’t rush this part—I’ve made that mistake more than once and ended up with a rhubarb landslide. Once they’re firm and cool, slice into squares and serve.
Baker’s Tips for Perfect Rhubarb Shortbread Bars
Mix the crust ingredients just until combined. Overworking it can make the base dense rather than tender.
Rhubarb releases a lot of liquid as it bakes, so make sure your crust is fully baked before adding the filling.
Don’t skip the cooling time. I usually bake these in the evening and let them cool overnight.
For super clean cuts, pop the bars into the fridge for 30 minutes before slicing.
Variations & Fun Twists
Here’s where you can start playing with flavors:
Strawberry-Rhubarb: Replace 1 cup of rhubarb with chopped strawberries. The classic combo never fails.
Add Citrus Zest: A teaspoon of orange or lemon zest in the filling adds brightness and complexity.
Crumble Top: Want more texture? Toss together a quick streusel (oats, butter, brown sugar) and sprinkle it over the filling before baking.
Gluten-Free Adaptation: Swap the flour for a 1:1 gluten-free blend. Just know the texture might be a bit softer.
If you’re into these kinds of rustic, fruit-forward desserts, check out my Rhubarb Crisp Recipe or this Moist Rhubarb Muffins Recipe.
How to Store and Freeze Rhubarb Shortbread Bars
These store beautifully, which makes them ideal for gifting or prepping ahead:
Room Temp: Keep in an airtight container for 2–3 days.
Refrigerator: Store for up to 5 days. I like to eat them chilled straight from the fridge—especially on warmer days.
Freezer: Freeze individually wrapped bars in a zip-top bag for up to 3 months. Thaw in the fridge overnight before serving.
Rhubarb Shortbread Bars: Frequently Asked Questions
Can I use frozen rhubarb?
Yes, and I do it all the time. Just make sure it’s thawed completely and well-drained to avoid sogginess.
Why is my shortbread crust tough?
Most often, that happens when the dough is overmixed. Mix just until it starts clumping—don’t knead or compact it like a pie crust.
What fruits can I pair with rhubarb?
Strawberries are a classic, but raspberries and apples also complement rhubarb beautifully. I’ve even tried it with peaches once—surprisingly good.
How do I know when the bars are done baking?
The edges will be lightly golden and the filling won’t jiggle when you move the pan. You can insert a toothpick near the center; it should come out mostly clean.
Let’s Bake Together
I’d love to know if you try these Rhubarb Shortbread Bars! Was it your first time baking with rhubarb? Did you stick to the classic recipe or add your own twist?
Leave a comment below, share your thoughts, and if you took pictures—definitely tag me. These bars are too pretty not to show off.
And if you’re loving the rhubarb vibe, don’t miss these:
Rhubarb Shortbread Bars
Ingredients
Shortbread Crust
- 1 cup 226g unsalted butter, softened
- ½ cup 100g granulated sugar
- 2 cups 240g all-purpose flour
- ¼ teaspoon salt
Rhubarb Filling
- 3 cups 375g fresh rhubarb, chopped
- 1 cup 200g granulated sugar
- 2 large eggs
- ¼ cup 30g all-purpose flour
- ½ teaspoon vanilla extract
- ¼ teaspoon salt
Instructions
- Preheat the Oven: Preheat to 350°F (175°C) and grease or line a 9x13-inch pan with parchment paper.
- Prepare the Shortbread Crust:
- In a bowl, cream butter and sugar until fluffy. Add flour and salt; mix until crumbly. Press evenly into the prepared pan.
- Bake for 15 minutes or until lightly golden around the edges. Let it cool slightly.
- Make the Rhubarb Filling:
- In another bowl, whisk sugar, eggs, flour, vanilla, and salt until smooth. Fold in chopped rhubarb.
- Assemble and Bake:
- Spread filling over the pre-baked crust. Bake an additional 40–45 minutes until set and golden.
- Cool and Slice:
- Let cool completely in the pan before slicing into squares. For cleaner slices, chill in the fridge before cutting.
Notes
- Fresh rhubarb yields the best texture, but frozen works if thawed and drained well.
- Don’t overmix the crust dough—it should be crumbly.
- Bars store well refrigerated for up to 5 days or frozen for up to 3 months.
- Optional add-ins: orange zest, strawberries, or a crumble topping for variation.
Thanks for baking with me—can’t wait to see what you create next.
