Rhubarb Cake is Better with Sumac

As the early summer sun brightens the landscapes of Maine, one of the first delights from the garden is the vibrant rhubarb. This tart vegetable is not only a herald of warmer days but also a versatile ingredient in our kitchens. While rhubarb and strawberries are a classic early summer pairing, we invite you to try adding sumac to this mix. The tangy and slightly zesty flavor of sumac offers a unique and delightful twist. Yossy Arefi’s Snacking Cakes cookbook includes a recipe for Rhubarb Crumb Cake with Sumac that brings these two unlikely companions together. And a crumb cake is simple to whip up since you don't even need any frosting! Whether you’re a seasoned baker or trying your hand at something new, this cake is a perfect way to celebrate the season’s early bounty.

Snacking Cakes by Yossy Arefi

"Rhubarb is my favorite vegetable masquerading as a fruit. It's tart and tangy, and makes my mouth pucker in the best possible way. I love folding rhubarb into all sorts of baked good, especially cakes topped with buttery crumb topping. This topping has an unexpected ingredient—dried sumac—which gives it a tart and fruity vibe."

Snacking cakes are meant to be easy to whip up from ingredients in your pantry. No fancy equipment required and most recipes only use one bowl! For this cake you'll need two, one for the cake and a second bowl for the crumb topping. The recipe is scaled for a 9" round or 8" square pan; double the recipe for a sheet cake. 

Sumac Rhubarb Crumb Cake Recipe

Recipe from Snacking Cakes by Yossy Arefi. Shared courtesy of Penguin Random House.

Note: If you don't have rhubarb, make this cake with a mix of berries!

Sumac Crumb


  • 1/2 cup (63g) all-purpose flour
  • 1/4 cup (50g) light brown sugar
  • 1/4 cup (23g) old-fashioned rolled oats
  • 2 teaspoons sumac
  • pinch of salt
  • 1/4 cup (55g) unsalted butter, very soft
  • Optional: sprinkle of vanilla salt for a crunchy finish

Rhubarb Cake


  • 1 lemon
  • 3/4 cup (150g) light brown sugar
  • 2 large eggs
  • 3/4 cup (165g) sour cream
  • 1/2 cup (113g) unsalted butter, melted
  • 1 tsp vanilla bean paste 
  • 1/2 tsp kosher salt
  • 1 1/4 cup (160g) all-purpose flour
  • 1 1/2 tsp baking powder
  • 1/2 tsp baking soda
  • 1 1/2 cups (150g) fresh chopped rhubarb, in 1/2-inch pieces (substitute berries if you don't have rhubarb)


  1. Position a rack in the center of your oven and preheat the oven to 350-degrees F. Butter or cast an 8-inch square baking pan with nonstick spray. Line the pan with strip of parchment paper that hangs over two of the edges (if using).
  2. MAKE THE TOPPING: Combine the flour, brown sugar, oats, sumac and salt in a small bowl. Add the butter and smoosh everything together with your fingers until the butter is evenly distributed and crumbs form.
  3. MAKE THE CAKE: Zest the lemon directly into a large bowl, add the brown sugar and eggs, and whisk until pale and foamy, about 1 minute. Add the sour cream, butter, vanilla, and salt. Whisk until smooth and emulsified.
  4. Add the flour, baking powder and baking soda to the bowl. Whisk until almost combined, then switch to a rubber spatula for the last few strokes; the batter will be quite thick. Fold in the rhubarb.
  5. Pour the batter into the prepared pan, tap the pan gently on the counter to release any air bubbles, and smooth the top of the batter with an offset spatula. Then sprinkle the topping over the batter. We like to add a sprinkle of vanilla salt, too!
  6. Bake the cake until puffed and golden, and a tester inserted into the center comes out clean, 50-60 minutes. Set the pan on a rack to cool for about 5 minutes. Then use the parchment paper to lift the cake out of the pan and set it on the rack to cool completely. Store the cake, well wrapped, at room temperature for up to two days.

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Our Favorite Cookbook for an Anytime Treat

Yossy Arefi is a recipe developer and food stylist who created the delightful book Snacking Cakes which celebrates the simplicity and joy of homemade cakes. The book features 50 recipes for easy-to-make, one-bowl cakes that are perfect for snacking or sharing with friends and family. 

Why we like it: One bowl cakes? No stand mixer? Cakes that are meant to be eaten anytime and easy enough for my seven year old to make? Yes please! Each recipe has recommended variations for glazes or frostings as well as alternative sizes. It's truly a "choose-you-own-adventure" cookbook.

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