This dessert belongs in everyone's "outdoor entertaining" file. The cake squares, embellished with moist fruit and a crunchy topping, are meant to be eaten out of hand.



Crumb Topping


Instructions Checklist
  • Cake: Preheat oven to 350 degrees, with rack in center position. Coat two 9-inch square cake pans with cooking spray, and line with parchment, leaving an overhang on 2 sides. Stir together rhubarb and 1 cup sugar; set aside to macerate.

  • Whisk together flour, baking powder, and salt. Beat together butter, remaining cup sugar, and the lemon zest until light and fluffy. Beat in eggs, 1 at a time, then beat in vanilla. Beat in flour mixture in 2 additions, alternating with sour cream, beginning and ending with flour mixture.

  • Crumb topping: Stir together flour, brown sugar, and salt. Add melted butter; stir to combine.

  • Divide batter between pans. Top with rhubarb mixture, and sprinkle with crumb topping. Bake until golden on top and cooked through, about 1 hour 5 minutes. Let cool completely in pans on wire racks, then lift cakes from pans using parchment. Remove parchment. Before serving, cut buckle into 2-inch squares.

Cook's Notes

Cakes can be wrapped in plastic wrap and stored at room temperature for 1 day.

Reviews (3)

82 Ratings
  • 5 star values: 40
  • 4 star values: 16
  • 3 star values: 12
  • 2 star values: 12
  • 1 star values: 2
Rating: 5 stars
This is my new favorite go-to rhubarb recipe. I did make a few tweaks: I decreased the amount of sugar I mixed with the rhubarb and added a few strawberries and a few tablespoons of my own strawberry-rhubarb jam. I also baked it in a 9x13 pan. The cake is so moist and delicious with just the right about of sweetness. With a scoop of vanilla ice cream it is perfection!
Rating: 5 stars
Wonderful recipe! I made a few adjustments - I used gluten free flour (trader joes brand), did half strawberries and half rhubarb, doubled the crumble top by adding 2/3 c. oatmeal and 1/2 stick extra butter. I baked it in one 9X11 pan for 50 minutes. So delicious! Moist, sweet but not too sweet, and great crumbly top. Will use again!
Rating: 5 stars
This really is very good - I made it several times last year and look forward to a good rhubarb crop this year to make more. I had never used rhubarb any other way but with strawberries in a pie, and it was such a treat to find this recipe.