Old-Fashioned Rhubarb Bars

Sweet and tangy rhubarb bars with a buttery shortbread crust and soft homemade filling

 

Rhubarb is one of those ingredients people either love or avoid completely. It’s tart, tangy, and unforgettable once you grow up eating it.

My mother always had several rhubarb plants growing in her garden. She loved the bright pink and green stalks because they added so much color along the edge of her yard. She used the rhubarb in cakes, jams, bars, and desserts all summer long.

Even the leaves never went to waste. Since rhubarb leaves are poisonous and cannot be eaten, she used them for crafting projects instead, coating them in cement to make garden decorations.

While going through her recipe box, we found this forgotten recipe for rhubarb bars—one I remembered her making years ago. They have the perfect balance of sweetness and tart rhubarb flavor layered over a buttery crust.

They’re simple, old-fashioned, and exactly the kind of dessert that disappears quickly once sliced.

Ingredients:

For the crust:
1 1/2 c. flour
1/4 c. powdered sugar
3/4 c. cold butter cubed

For the filling;
3 large eggs, lightly beaten
2 c. white sugar
1/2 c.  flour
1/2 tsp. salt
4 c. rhubarb, diced

Directions:

Preheat oven to 350°F. Grease a 9x13-inch baking pan.

In a large mixing bowl, whisk together eggs, sugar, flour, and salt until smooth.

Stir in the diced rhubarb. Set aside while preparing the crust.

In a medium bowl, combine flour and powdered sugar.

Cut in the cold butter using a pastry blender or two knives until the mixture resembles coarse crumbs.

Press the mixture evenly into the prepared baking pan.

Bake for 10–12 minutes, or until lightly golden.

Remove from the oven.

Carefully pour the rhubarb filling evenly over the hot crust.

Reduce oven temperature to 325°F.

Return the pan to the oven and bake for 30–35 minutes, or until the filling is set and no longer jiggly in the center.

Cool at room temperature for about 30 minutes.

Refrigerate until fully chilled before slicing into bars.

Tips for Best Success:

• Use cold butter for the flakiest crust
• Dice rhubarb evenly for consistent texture
• Don’t overbake or the filling may crack
• Chill completely before cutting for clean bars
• Line the pan with parchment paper for easier removal

Variations & Substitutions:

• Add Strawberries: Replace 1 cup rhubarb with strawberries
• Extra Flavor: Add vanilla or cinnamon
• Topping Option: Dust with powdered sugar before serving
• Gluten-Free: Use a 1:1 gluten-free flour blend

Serving Suggestions:

• Serve chilled or room temperature
• Pair with coffee or tea
• Top with whipped cream or vanilla ice cream
• Great for spring and summer gatherings

How to Store:

• Store covered in the refrigerator
• Best enjoyed within 4–5 days
• Bars can be frozen for up to 2 months

Frequently Asked Questions:

Can I use frozen rhubarb?
Yes. Thaw and drain excess liquid first.

Why are my bars runny?
They likely need more baking time or more chilling time.

Can I reduce the sugar?
Yes, though rhubarb is naturally very tart.

Do I need to peel rhubarb?
No, just wash and trim it well.

Are rhubarb leaves safe to eat?
No. Rhubarb leaves are poisonous and should never be consumed.