Almost every year, as soon as the weather gets warm, I become obsessed with a simple, single layer cake that can be made in little time and that I promise will be all you need to be welcome at any picnic/barbecue/cook out/pot-luck that summer.
Three years ago, it was a raspberry buttermilk cake, which was the equivalent of taking a single, thin layer from the very best yellow birthday cake you’ve ever had, scattering fresh raspberries over it and baking it until bronzed and perfect. Needless to say, it went on repeat. Later that summer, it was blueberry boy bait, a cake so decadent and buttery I briefly questioned if it had too much butter, then checked my pulse, realized any talk of too much butter was simply madness, and enjoyed the cake thoroughly for as long as the blueberries lasted. (Also, it worked.) Last year I become enamored with something I called a strawberry summer cake. Round and finely crumbed, yet almost butter-slathered-hot-biscuit in texture, it works best with just-picked and borderline-overripe strawberries that, when baked, nearly dissolve into jammy puddles throughout the cake. I also found that I liked it with some of the regular flour replaced with barley flour; just trust me, it works.
And even though this category of cakes — the ones that you start baking on repeat over Memorial Day weekend (right after you take the cover of the grill and the tags off the season’s first sundress), and tuck away for the winter when apples emerge after Labor Day — was at capacity, that the cakes listed above are really all anyone should ever need, I have never known when to leave well enough alone and I’m so glad because this rhubarb snacking cake is my absolute favorite yet. Case closed. At least until next summer.
Because this cake, it simply wins. Part buckle, part streusel cake and part crumb bar, it’s the kind of nubby cake you serve in 2×2-inch squares on napkins, standing in the shade of a backyard. Although only 3/4-inch high, it manages to contain in that diminutive height the three finest elements of simple cakes loudly enough that you won’t even wish it were taller. The base is a thin layer of the most moist, tender and plush yellow cake that has ever graced this URL, fragrant with butter, a bit of lemon zest and the faintest amount of ground ginger. This is followed by a layer of sweet — but not so sweet that it forgets its tart roots — rhubarb that’s been macerated with sugar and lemon and baked into a jammy layer that’s closer to the inside of a crumb bar than the standard handful of berries normally speckled throughout summer cake. It comes thisclose to overwhelming the cake below it, but stops just in time. You won’t mind. The cake is finished with a brown sugar crumble with a pinch of cinnamon and when these three elements bake together, you’re done. You won’t need another go-to dessert recipe this summer, which means that your time is now free to play Frisbee, stare at the deep blue sea, invent cocktails, gather freckles across noses, and drag your sandy, sticky selves back inside at night to sleep soundly, then do it all again tomorrow.
One year ago: Spring Salad with New Potatoes
Two years ago: Strawberry Brown Butter Bettys and Shaved Asparagus Pizza
Three years ago: Grilled Shrimp Cocktail and Graham Crakcers
Four years ago: Haricot Vert with Shallots
Five years ago: Strawberry Rhubarb Crumble
Rhubarb Snacking Cake
This cake was inspired by one I saw in Martha Stewart Living this month, but I changed a lot. Instead of making it in two 9-inch square pans, I baked it in a single 9×13, which is closer to the size I think is fitting for a picnic or pot luck and less work. I 2/3-erd the cake portion, because I wanted it to be thin, skipped the vanilla (which I think can be occasionally clashy with rhubarb) and added a pinch of ginger (which I think goes wonderfully) but not so much that the cake is by any means “gingery.” I increased the baking powder as well, just a hair, because it seemed too little for the flour volume. I didn’t scale down the rhubarb accordingly, but I did add lemon and reduce the sugar because I like it when rhubarb can still shine like its tart little self. I increased the crumb proportionally and I’m glad I did because, really, you can never enough crumb (and once baked, it keeps that extra rhubarb from running right off the cake) and I added a pinch of cinnamon to the crumb because, yes, it’s just happy there.
1 1/4 pound (565 grams) rhubarb, trimmed and cut into 1/2-inch lengths on the diagonal
1 1/3 cup (265 grams) granulated sugar, divided
1 tablespoon lemon juice (psst, skip ahead and zest it for the cake before you cut it)
1/2 cup (1 stick, 4 ounces or 115 grams) unsalted butter, softened
1/2 teaspoon finely grated lemon zest
2 large eggs
1 1/3 cups (165 grams) all-purpose flour
1 teaspoon baking powder
3/4 teaspoon table salt
1/4 teaspoon ground ginger
1/3 cup (80 grams) sour cream
1 cup (125 grams) all-purpose flour
1/4 cup (50 grams) light brown sugar
1/8 teaspoon table salt
1/4 teaspoon ground cinnamon
4 tablespoons (1/2 stick, 2 ounces, or 55 grams) unsalted butter, melted
Make the cake: Preheat your oven to 350°F. Coat the bottom and sides of a 9×13-inch baking pan with butter or a nonstick cooking spray, then line the bottom with parchment paper, extending the lengths up two sides. (It will look like a sling). Stir together rhubarb, lemon juice and 2/3 cup sugar and set aside. Beat butter, remaining sugar and lemon zest with an electric mixer until light and fluffy. Add eggs, one at at time, scraping down the sides after each addition. Whisk together flour, baking powder, 3/4 teaspoon table salt and ground ginger together in a small bowl. Add one-third of this mixture to the batter, mixing until just combined. Continue, adding half the sour cream, the second third of the flour mixture, the remaining sour cream, and then the remaining flour mixture, mixing between each addition until just combined.
Dollop batter over prepared pan, then use a spatula — offset, if you have one, makes this easiest — to spread the cake into an even, thin layer. Pour the rhubarb mixture over the cake, spreading it into an even layer (most pieces should fit in a tight, single layer).
Stir together the crumb mixture, first whisking the flour, brown sugar, table salt and cinnamon together, then stirring in the melted butter with a spoon or fork. Scatter evenly over rhubarb layer. Bake cake in preheated oven for 50 to 60 minutes. The cake is done when a tester comes out free of the wet cake batter below. It will be golden on top. Cool completely in the pan on a rack.
Cut the two exposed sides of the cake free of the pan, if needed, then use the parchment “sling” to remove the cake from the pan. Cut into 2-inch squares and go ahead and eat the first one standing up. (If it’s written into the recipe, it’s not “sneaking” a piece but, in fact, following orders, right?) Share the rest with friends. Cake keeps at room temperature for a few days, but I didn’t mind it at all from the fridge, where I kept it covered tightly.