Just like Jeni’s Brambleberry Crisp, this cake boasts the perfect ratio of jammy fruit to crunchy oat streusel
Having grown up in Columbus, Ohio, Graeter’s and Jeni’s were always my go-to spots for grabbing a cold, creamy treat on summer nights. While my friends tended to gravitate toward Jeni’s ’gram-ready vibes and unexpected flavors (goat cheese with red cherries, anyone?), my dad has always been an outspoken Graeter’s devotee, preferring their old-school, no-frills setup and simple, classic options (their cookies and cream can’t be beat, in my opinion). Though I’m constantly vacillating between the two (I’m currently in a Graeter’s phase), I remember falling in love with Jeni’s iconic Brambleberry Crisp flavor the first time I had it years ago: Each pie-like scoop is swirled with the perfect ratio of brambleberry jam and chunks of brown sugar oat streusel.
This month’s cake is directly inspired by my favorite Jeni’s flavor and doubles as my ode to long, slow (and quiet) Ohio summers. Made in an 8-by-8-inch pan, the lemon-kissed sour cream cake is topped with ripe summer berries (I use a combination of raspberries and blackberries) that bake up just jammy enough while retaining some of their structure. The whole thing gets showered in an oat streusel, which turned out to be my favorite part of the cake and the bane of my existence during the development process: Iteration after iteration, my streusel kept melting and/or sinking into the cake. While all the testers ended up tasting fine (there were a lot of them), I was determined to create a cake that looked the part, too.
After some deep-dive research, I increased the flour and cut down on the butter in the streusel, and followed the very knowledgeable Rose Levy Beranbaum’s helpful tip to sprinkle on the topping 30 minutes into baking. The reason behind this, as I learned from my conversation with cookbook author and food stylist Yossy Arefi (another smart, wonderful pastry person), is that it’s imperative for the cake to have enough structure to support the weight of the streusel. Allowing the cake to set in the oven a bit before adding the streusel helps to create a sturdier base that won’t immediately swallow the topping. Thanks to these pastry experts, I ended up with the streusel-laden cake I envisioned.
This cake celebrates summer in all its ripe, bountiful glory: The crunchy, just-sweet-enough oat streusel gives way to tender cake and baked berries, with cinnamon and lemon zest adding lovely notes of nuance. If you want something a little more over-the-top, serve squares of the cake with a scoop of high-quality vanilla ice cream, lightly sweetened whipped cream — or if you’re feeling extra (basically me, all the time), alongside a pint of Jeni’s Brambleberry Crisp itself. There’s really no better way to soak up this fleeting, delightful season.
Summer Berry Streusel Cake
Makes one 8-by-8-inch cake
For the oat streusel:
¼ cup (50 grams) light brown sugar
⅓ cup (47 grams) all-purpose flour
⅓ cup (30 grams) old-fashioned rolled oats
¼ teaspoon ground cinnamon
⅛ teaspoon kosher salt
3 tablespoons unsalted butter, cold and cut into small cubes
For the cake:
1 cup (140 grams) all-purpose flour
1 teaspoon baking powder
¼ teaspoon baking soda
¼ teaspoon kosher salt
½ cup (1 stick) unsalted butter, softened
⅔ cup (133 grams) granulated sugar
⅓ cup (67 grams) light brown sugar, packed
1 teaspoon finely grated lemon zest
2 large eggs, at room temperature
1 teaspoon vanilla extract
½ cup (114 grams) full-fat sour cream, at room temperature
¼ cup whole milk, at room temperature
6 ounces ripe summer berries (raspberries, blackberries, or a combination)
Step 1: Preheat the oven to 350 degrees. Lightly grease an 8-by-8-inch square cake pan with nonstick cooking spray. Line the bottom with parchment paper, leaving a 2-inch overhang on the sides (to make it easier to remove the cake after baking), and grease the parchment.
Step 2: Make the oat streusel: In a medium bowl, combine the sugar, flour, oats, cinnamon, and salt and mix thoroughly with your hands. Work the butter into the dry ingredients with your fingers until the streusel resembles wet sand and clumps together when you squeeze it (some small bits of butter are fine). Chill the streusel in the refrigerator until ready to use.
Step 3: In a medium bowl, whisk together the flour, baking powder, baking soda, and salt.
Step 4: In a large bowl, beat the butter with an electric hand mixer or in a stand mixer fitted with the paddle attachment until smooth. Add the sugars and lemon zest and cream the mixture until light and fluffy, 2 to 3 minutes. Scrape down the bowl with a rubber spatula.
Step 5: Beat in the eggs one at a time, scraping down the bowl after each addition. Add the vanilla extract and beat until combined.
Step 6: Add half of the dry ingredients to the bowl and beat until just combined. Carefully beat in the sour cream and milk, scrape down the bowl, then add the rest of the dry ingredients and beat until just combined and the batter is smooth. Take care not to overmix.
Step 7: Scrape the batter into the prepared pan and smooth the surface with a small offset spatula. Sprinkle the berries evenly on top of the batter. The batter will rise around them, so there’s no need to press them down.
Step 8: Bake the cake for 35 minutes, then remove the pan from the oven and quickly but gently sprinkle the streusel on top in an even layer — the cake will be very delicate. Carefully return the cake to the oven and bake for 17 to 20 more minutes, until a toothpick inserted in the center comes out nearly clean or with a few moist crumbs.
Step 9: Let the cake cool in the pan for at least 30 minutes, then gently run a small offset spatula around the edges to loosen. Using the parchment sling to assist, gently transfer the cake to a rack to cool completely before slicing and serving.
Joy Cho is a freelance writer, recipe developer, and pastry chef based in New York City.
Celeste Noche is a Filipino American food, travel, and portrait photographer based between Portland, Oregon, and San Francisco.
Recipe tested by Deena Prichep