Rhubarb buckle on a plate.

In the wonderful world of crumb-topped, baked-fruit desserts, buckles are new to me. And I’m a fan. I love how the sandy, buttery topping melts into the stewed fruit, which all sinks — buckles! — into the base. And I like that I can eat it as I would a brownie, out of hand, making for easy snacking morning, noon and night.

Martha said it best: “This dessert belongs in everyone’s outdoor entertaining file.”

This batter, made with eggs, sour cream and melted butter yields the perfect base — not too cakey, not too crisp, a slightly sweet, perfectly sturdy layer that really allows the rhubarb to shine.

If you are not a fan of rhubarb or if you blink and miss rhubarb season altogether, don’t despair. I suspect blueberries and peaches and every other wonderful stone fruit and berry will make dream-worthy buckles all summer long.

How to Make a Rhubarb Buckle

Gather your ingredients:

The ingredients to make rhubarb buckle.

First: stir together the crumb topping: brown sugar, flour, melted butter and a pinch of salt.

Just-mixed crumb topping.

Next, whisk together your dry ingredients: flour, salt, baking powder, and sugar.

Whisking the dry ingredients for the rhubarb buckle.

Add sour cream, melted butter, eggs, and vanilla.

Adding the wet ingredients to the bowl for the rhubarb buckle.

Stir to combine.

Just-mixed batter for the rhubarb buckle.

Fold in the rhubarb.

Adding the rhubarb to the batter for the buckle.

Transfer batter to a buttered and parchment-lined 9-inch pan.

Batter for the rhubarb buckle in a square pan.

Top with the crumb topping; then transfer to the oven.

Adding the crumb topping to the rhubarb buckle.

Bake for about 45 minutes or until evenly golden and an inserted cake tester comes out clean.

Just-baked rhubarb buckle.

Let cool briefly before cutting and serving.

Rhubarb buckle on a plate.
clock clock iconcutlery cutlery iconflag flag iconfolder folder iconinstagram instagram iconpinterest pinterest iconfacebook facebook iconprint print iconsquares squares iconheart heart iconheart solid heart solid icon
Rhubarb buckle on a plate.

Rhubarb Buckle

5 Stars 4 Stars 3 Stars 2 Stars 1 Star

5 from 8 reviews

Save Recipe



This is an updated post from two older posts. If you are looking for the old recipe that called for a shortbread crust, find it here


For the crumb topping:

  • 1/2 cup (64 g) all-purpose flour
  • 1/4 cup light-brown sugar
  • pinch salt
  • 4 tablespoons unsalted butter, melted

For the buckle: 

  • 1 teaspoon baking powder
  • 1.5 cups (192 g) flour
  • 1/2 teaspoon salt
  • 1 cup sugar
  • 4 tablespoons melted butter
  • 2 eggs, beaten
  • 1/2 cup sour cream
  • 1 teaspoon vanilla extract
  • 12 oz (3 cups) diced rhubarb


  1. Preheat oven to 350ºF with rack in center position. Line a 9-inch square cake pan with parchment paper.
  2. Make the crumb topping: In a medium bowl, stir together the 1/2 cup flour, brown sugar, pinch salt, and 4 tablespoons melted butter. Transfer to the fridge. 
  3. In a large bowl, whisk together the baking powder, 1.5 cups flour, salt, and sugar. Add the 4 tablespoons melted butter, eggs, sour cream, and vanilla. Stir to combine. Fold in the diced rhubarb.
  4. Transfer batter to prepared pan. Top with crumb topping. Transfer to the oven until crumb topping is golden and cake is done, about 45 to 55 minutes. Let cool 15 minutes in pan before cutting and serving. 
  • Prep Time: 20 minutes
  • Cook Time: 1 hour
  • Category: Dessert
  • Method: Oven/Baking
  • Cuisine: American