Name: Rhubarb Honey Buttercream Swirl Bars Recipe
Prep time: 20 min
Cook time: 10 min
Total time: 4 h 30 min
Cuisine: American
Ingredients: 1 1/2 cups graham cracker crumbs; 1/4 cup sugar; 1/2 cup unsalted butter, melted; 2 cups chopped rhubarb; 1/4 cup honey; 2 tablespoons sugar; 1 tablespoon lemon juice; 1/2 cup unsalted butter, softened; 2 cups powdered sugar; 2 tablespoons honey; 1 teaspoon vanilla extract; 2–3 tablespoons milk (as needed for consistency)

Jump to Recipe· 4.9 from 25 reviews

If you’re searching for a showstopping treat that balances bright, tangy fruit with creamy richness, let me introduce you to these magical Rhubarb Honey Buttercream Swirl Bars. Each bite is a beautiful collision of buttery graham cracker crust, luscious swirls of honey-kissed buttercream, and vibrant pockets of tart-sweet rhubarb—perfect for spring brunches, Mother’s Day, or just when you’re feeling a little whimsical. Whether you’re a rhubarb lover or looking to try something unique, this recipe is a delicious twist on classic dessert bars, guaranteed to delight friends and family alike.

Rhubarb Honey Buttercream Swirl Bars Recipe - Recipe Image

Ingredients You’ll Need

The magic of Rhubarb Honey Buttercream Swirl Bars lies in a handful of simple ingredients, each with an important role. From the golden graham cracker crust to the vibrant rhubarb and dreamy buttercream, every component brings taste, color, or dessert-defining texture.

Graham cracker crumbs: These form the buttery, crunchy base that holds everything together and adds irresistible flavor.
Sugar: Just enough to sweeten the crust and fruit without overpowering the rhubarb’s tang.
Unsalted butter, melted: This binds the crumb crust, lending richness and that beloved cookie flavor.
Chopped rhubarb: The tart star of the show that adds lively color and zing to each bar.
Honey: Infuses the rhubarb mixture and buttercream with gentle floral sweetness that’s lighter than processed sugar.
Lemon juice: Brightens the rhubarb and balances the honey, making the flavors pop.
Unsalted butter, softened: This is the dreamy base of the buttercream, making every swirl velvety smooth.
Powdered sugar: The secret to a silky, cloud-like buttercream topping.
Vanilla extract: A splash for warmth and depth—don’t skip it!
Milk: Added as needed for the perfect buttercream swirl consistency—smooth, not runny.

How to Make Rhubarb Honey Buttercream Swirl Bars

Step 1: Make the Crust

Start by mixing your graham cracker crumbs, sugar, and melted butter in a medium bowl until everything is evenly coated and resembles damp sand. Press this delightful mixture firmly into the bottom of a 9×9-inch baking dish, making sure to reach right up to the corners for maximum structure. This buttery, crunchy base will be the tasty foundation for your bars.

Step 2: Cook the Rhubarb Layer

In a small saucepan over medium heat, combine the chopped rhubarb, honey, sugar, and a squeeze of lemon juice. Stir occasionally as the rhubarb releases its juices and softens, transforming the mixture into a fragrant, ruby-red compote in about 10 minutes. Allow it to cool just a bit—this step infuses the bars with their signature tart-sweet oomph.

Step 3: Prepare the Buttercream Swirl

While your rhubarb cools, beat together softened butter, powdered sugar, honey, and vanilla in a mixing bowl until you have a smooth, creamy frosting. Gradually add milk, just a tablespoon at a time, until the buttercream is fluffy and spreadable, but not runny. This honey buttercream is the secret weapon that sets these Rhubarb Honey Buttercream Swirl Bars apart.

Step 4: Assemble the Bars

Now for the fun: spread the cooled rhubarb mixture evenly over the prepared crust. Drop generous spoonfuls of that luscious buttercream all over, then gently swirl with a knife or skewer. Don’t overmix—you want pockets and ribbons of creaminess running through every piece!

Step 5: Chill

Pop the pan into the refrigerator for at least 4 hours or until the bars are nice and firm. Patience pays off here! Chilling helps the layers set for clean slicing and lets all the flavors mingle beautifully.

Step 6: Serve

Once chilled, slice your Rhubarb Honey Buttercream Swirl Bars into neat squares. Serve them cold for the ultimate creamy-tangy experience that melts in your mouth.

How to Serve Rhubarb Honey Buttercream Swirl Bars

Garnishes

A light dusting of powdered sugar, a drizzle of extra honey, or a sprinkle of finely grated lemon zest adds elegance and a pop of color. For a festive look, adorn each bar with a tiny piece of candied rhubarb or edible flowers—totally optional, but utterly charming.

Side Dishes

Rhubarb Honey Buttercream Swirl Bars pair like a dream with fresh berries, a scoop of vanilla gelato, or a cup of bright, floral tea. If you want to add a savory note to your dessert spread, a tangy goat cheese or creamy brie on the side makes for a sophisticated finish.

Creative Ways to Present

Serve the bars stacked on a pedestal cake stand for a striking centerpiece, or offer individual portions on colorful plates for a garden-party vibe. For gatherings, try cutting them into mini-bite squares and nestling each one in a cupcake liner—adorable and easy for guests to nibble.

Make Ahead and Storage

Storing Leftovers

Place any leftover Rhubarb Honey Buttercream Swirl Bars in an airtight container and refrigerate for up to five days. The chill keeps both the buttercream and rhubarb fresh, and the bars actually taste even better after a day or two as the flavors meld together.

Freezing

Want to make these ahead? You can freeze the assembled bars before slicing. Wrap the whole chilled block tightly in plastic wrap and aluminum foil, or layer individual bars between parchment in a freezer-safe container. They’ll keep perfectly for up to three months—just thaw overnight in the fridge before serving.

Reheating

There’s no need to reheat these bars; in fact, they’re best enjoyed cold right from the fridge. If you do prefer them closer to room temperature, simply let them sit out for 10 minutes before serving.

FAQs

Can I use frozen rhubarb instead of fresh?

Absolutely! If using frozen rhubarb, thaw it and drain off any excess liquid before cooking. The results will be just as delicious, making Rhubarb Honey Buttercream Swirl Bars accessible year-round.

Can I substitute the graham cracker crust with something gluten-free?

Yes, you can use gluten-free graham crackers or even almond flour mixed with a touch of sugar and butter for a similar tasty, crumbly base. Just make sure to press the mixture firmly for best results.

How do you get those pretty swirl patterns?

The key is to gently swirl the buttercream into the rhubarb layer using a knife or skewer. Aim for a few broad, sweeping motions rather than over-mixing to preserve gorgeous ribbons of color and flavor throughout the Rhubarb Honey Buttercream Swirl Bars.

Can I add strawberries to the rhubarb layer?

Definitely! Adding a handful of chopped strawberries will complement the rhubarb’s tartness and give the bars a sweeter, more summery flavor. Just cook the mixture as directed and enjoy an extra pop of color.

Can I prepare these bars in advance for a party?

Rhubarb Honey Buttercream Swirl Bars are ideal for making ahead, as they need to chill before serving. Assemble and store in the fridge up to two days in advance; just slice and garnish before your guests arrive for a stress-free, stunning dessert.

Final Thoughts

I hope you’re as excited as I am to share these Rhubarb Honey Buttercream Swirl Bars with your favorite people. Bright, creamy, and absolutely unforgettable—give this recipe a try and let the swirls of joy take center stage at your next gathering!