Lemon Rhubarb Dessert Bars Recipe is a bright, tangy treat with a buttery crust, layered with sweet lemon and rhubarb—perfect for spring!
Ingredients You’ll Need
With just a handful of straightforward ingredients, making Lemon Rhubarb Dessert Bars is as easy as can be. Each component brings something essential to the party: from the crisp crust to the zesty, colorful filling, every ingredient deserves its moment in the spotlight.
- All-purpose flour: Gives your bars structure and that perfect, tender bite—don’t substitute whole wheat here or you’ll lose the delicate crumb.
- Powdered sugar: Sweetens the shortbread base and ensures a fine, melt-in-your-mouth texture.
- Salt: Enhances all the flavors—never underestimate this pinch!
- Unsalted butter: The magic ingredient for a rich, buttery, and oh-so-flaky crust; it must be cold for best results.
- Chopped rhubarb: Brings that signature tart flavor and a swoosh of lovely pink color—fresh or frozen (thawed and drained) both work.
- Granulated sugar: Balances the rhubarb’s tartness and sweetens the lemon filling just right.
- Eggs: The key to a silky, custard-like filling; they hold everything together and add richness.
- Lemon zest and juice: Provides unbeatable brightness and tang, elevating the rhubarb to new heights.
- Baking powder: Adds a gentle lift so your filling stays light, not dense.
- Optional: powdered sugar for dusting: A final shower of sweetness for that classic “bakery fresh” look.
How to Make Lemon Rhubarb Dessert Bars
Step 1: Prep Your Pan and Preheat the Oven
Start by lining a 9×9-inch baking pan with parchment paper, leaving an overhang so you can easily lift your Lemon Rhubarb Dessert Bars out later. Preheat your oven to 350°F (175°C) and let it come up to temperature while you work on the crust. This simple step avoids sticking and helps you achieve picture-perfect squares every time.
Step 2: Whip Up the Buttery Shortbread Crust
In a medium bowl, whisk together the all-purpose flour, powdered sugar, and salt. Then add the cold, cubed butter and cut it in with your fingertips or a pastry cutter until the mixture looks like coarse crumbs. This keeps the crust light and short—think a firm, buttery base that won’t get soggy under the filling.
Step 3: Bake the Crust
Press the shortbread mixture into the bottom of your prepared pan, smoothing it into an even layer. Pop it in the oven for 15–18 minutes, or until the edges look just barely golden. Pre-baking the crust ensures the Lemon Rhubarb Dessert Bars have a sturdy foundation and crisp bite.
Step 4: Prepare the Rhubarb and Lemon Filling
While your crust bakes, toss the chopped rhubarb with granulated sugar and let it sit for about 10 minutes. This little rest releases the rhubarb’s juices, which helps the filling stay moist and jewel-bright.
Step 5: Mix the Custardy Lemon Batter
In a separate bowl, whisk together eggs, lemon juice and zest, flour, baking powder, and a pinch of salt until your mixture is smooth. The lemon’s fragrance will start to bloom here, promising a sunny bar that tastes as lively as it looks.
Step 6: Combine and Pour
Gently fold the rhubarb—along with those rosy juices—into the lemon batter. Stir just until combined. Removing the crust from the oven, pour the filling on top while it’s still hot; this helps everything set up beautifully together.
Step 7: Bake Again
Return the pan to the oven and bake for 25–30 minutes. The Lemon Rhubarb Dessert Bars are done when the center is set and the top is lightly golden. Resist the urge to over-bake; you want the filling to stay delicately custardy, not dry.
Step 8: Cool and Slice
Let the bars cool completely in the pan on a wire rack. This is the hardest part—waiting! Once cooled, lift the bars out using the parchment overhang and cut into clean squares. For a bakery-worthy finish, dust with powdered sugar just before serving.
How to Serve Lemon Rhubarb Dessert Bars
Garnishes
For a little extra flair, a quick dusting of powdered sugar is a classic move. If you’re feeling fancy, add some thin lemon slices or curls of lemon zest on top. A sprig of mint or even a dollop of softly whipped cream can elevate the Lemon Rhubarb Dessert Bars from a casual treat to a stylish dessert centerpiece.
Side Dishes
These bars pair beautifully with a hot cup of tea or a scoop of vanilla ice cream. For an afternoon gathering, serve alongside a fresh berry salad or some sliced strawberries. Their sweet-tart notes also play well with lightly sweetened yogurt or crème fraîche.
Creative Ways to Present
Stack the Lemon Rhubarb Dessert Bars on a pretty platter for a buffet, or pack into a parchment-lined box for a picnic-ready treat. Cut them into triangles or diamond shapes to switch things up, or serve single bars in cupcake liners at a bake sale for easy grabbing.
Make Ahead and Storage
Storing Leftovers
Once fully cooled, store leftover bars in an airtight container in the refrigerator. They’ll keep their flavor and moist texture for up to 4 days, making them perfect for make-ahead entertaining or sneaking a bar on a busy weekday.
Freezing
You can absolutely freeze Lemon Rhubarb Dessert Bars! Simply wrap individual bars tightly in plastic wrap, then place them in a freezer-safe bag or container. They’ll hold up for about two months—just thaw overnight in the fridge when you’re ready for a treat.
Reheating
While these bars are delightful chilled or at room temperature, you can bring out their flavor by letting them sit on the counter for 30 minutes before serving. If you want them warm, give each bar a super quick zap in the microwave (about 10 seconds) before topping with powdered sugar.
FAQs
Can I use frozen rhubarb instead of fresh?
Absolutely! Just be sure to thaw and drain it well to prevent excess moisture. Frozen rhubarb works beautifully in Lemon Rhubarb Dessert Bars and delivers the same lovely tartness and color.
How do I know when the bars are done baking?
You’ll know the Lemon Rhubarb Dessert Bars are ready when the filling is set and the top is gently golden. It shouldn’t jiggle in the center when you gently shake the pan, but be careful not to over-bake to avoid a rubbery texture.
Is the crust supposed to be crispy or soft?
The shortbread crust should be crisp and firm yet tender, standing up to the juicy filling without turning soggy. Baking it before adding the filling ensures you get that irresistible bite every time.
Can I make these gluten-free?
Yes, you can substitute a 1:1 gluten-free flour blend for the all-purpose flour with good results. Just be aware that the texture may be slightly different, but you’ll still get all that bright, tangy flavor.
What’s the best way to cut clean bars?
For those perfect, bakery-style squares, chill the Lemon Rhubarb Dessert Bars completely before slicing. Use a sharp, damp knife and wipe it clean between each cut for the sharpest edges.
Final Thoughts
If you’re searching for a dessert that balances cheerful tartness with sunny sweetness, these Lemon Rhubarb Dessert Bars are a must-bake. I hope you’ll give them a try—there’s nothing quite like the magic of rhubarb and lemon coming together in every bite!
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Lemon Rhubarb Dessert Bars Recipe
- Total Time: 1 hr
- Yield: 16 bars
- Diet: Vegetarian
Description
Lemon Rhubarb Dessert Bars Recipe is a delightful blend of rhubarb and lemon layered over a buttery crust—perfectly sweet, tangy, and refreshing.
Ingredients
For the Crust
- 1 ½ cups all-purpose flour
- ½ cup powdered sugar
- ½ teaspoon salt
- 1 cup cold unsalted butter, cubed
For the Filling
- 2 cups chopped rhubarb (fresh or frozen, thawed and drained)
- 1 cup granulated sugar
- 2 large eggs
- ¾ cup all-purpose flour
- Zest and juice of 1 large lemon (about 2 tablespoons juice + 1 teaspoon zest)
- ½ teaspoon baking powder
- Pinch of salt
Optional Topping
- Powdered sugar, for dusting
Instructions
- Prepare the Pan. Preheat your oven to 350°F (175°C). Line a 9×9-inch baking pan with parchment paper, leaving some overhang on the sides to make removing the bars easier later.
- Make the Crust. In a medium bowl, whisk together 1½ cups flour, powdered sugar, and ½ teaspoon salt. Add the cold, cubed butter. Use a pastry cutter or your fingers to cut the butter into the dry ingredients until the mixture resembles coarse crumbs.
- Par-Bake the Crust. Press the crust mixture firmly and evenly into the bottom of the prepared pan. Bake for 15–18 minutes, until the edges begin to turn lightly golden.
- Prep the Rhubarb. While the crust is baking, combine chopped rhubarb and granulated sugar in a bowl. Let it sit for 10 minutes to macerate, then stir to help the rhubarb release its juices.
- Make the Lemon Filling. In a separate bowl, whisk together the eggs, lemon juice, lemon zest, ¾ cup flour, baking powder, and a pinch of salt until the mixture is smooth and well-blended.
- Combine Rhubarb and Filling. Gently fold the macerated rhubarb, along with any juices, into the lemon filling batter.
- Bake the Bars. Pour the rhubarb lemon filling over the hot crust as soon as it comes out of the oven. Spread evenly. Return the pan to the oven and bake for 25–30 minutes, or until the filling is set and lightly golden on top.
- Cool and Serve. Let the bars cool completely in the pan on a wire rack. Use the parchment overhang to lift the bars out, then cut into 16 squares. Dust with powdered sugar before serving, if desired.
Notes
- For perfectly clean squares, chill the bars in the fridge for 30–60 minutes before slicing.
- You can substitute frozen rhubarb—just thaw and drain it well first.
- For extra color and flavor, add a handful of chopped strawberries to the filling.
- Keep leftovers stored in an airtight container in the refrigerator for up to 4 days.
- Prep Time: 15 mins
- Cook Time: 45 mins
- Category: Desserts
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 bar
- Calories: 230
- Sugar: 18g
- Sodium: 80mg
- Fat: 10g
- Saturated Fat: 6g
- Unsaturated Fat: 3.5g
- Trans Fat: 0g
- Carbohydrates: 32g
- Fiber: 1g
- Protein: 2g
- Cholesterol: 37mg