Blueberry Buckle with Cornflake Streusel

Ingredients

• 1 3/4 cups All-purpose flour (Divided: 1 cup for streusel, 3/4 cup for cake)
• 1/2 cup Light brown sugar (Packed, for streusel)
• 18 tablespoons Unsalted butter (8 tbsp (1 stick) for streusel, 10 tbsp for cake, both at room temperature)
• 2 1/4 teaspoons Kosher salt (2 tsp for cake (Diamond Crystal; use 1 tsp if Morton), 1/4 tsp for streusel)
• 1 teaspoon Ground cinnamon (For streusel)
• 1 cup Corn flakes (Crushed by hand, for streusel)
• 3/4 cup Granulated sugar (For cake)
• 3/4 cup Buttermilk (Room temperature)
• 2 large Eggs (Room temperature)
• 1 1/2 teaspoons Baking powder (For cake)
• 1/2 teaspoon Baking soda (For cake)
• 1/3 cup Coarse ground cornmeal (For cake)
• 1.5 pounds Blueberries (Fresh or frozen (two 12-oz or four 6-oz packages))
• 2 teaspoons Lemon zest (From 1 small lemon)
• 2 teaspoons Vanilla extract (For cake)
• 1 sheet Parchment paper (For lining pan)

Instructions

1. Make the Streusel Topping

   In a medium bowl, combine 1 cup all-purpose flour, 1/2 cup packed light brown sugar, 1/4 tsp kosher salt, and 1 tsp cinnamon. Mix well. Add 8 tbsp (1 stick) unsalted butter, cubed and at room temperature. Using your fingers, work the butter into the dry ingredients until the mixture forms moist, clumpy crumbs with no dry spots. Add 1 cup crushed corn flakes and gently toss to combine. Set aside.

   Time: PT8M

2. Prepare the Pan

   Brush the bottom and sides of a 10-inch springform pan with a little softened butter. Line the bottom with a round of parchment paper cut to fit. Smooth out any air bubbles and brush the parchment with a bit more butter.

   Time: PT4M

3. Mix Dry Ingredients for Cake

   In a medium bowl, whisk together 3/4 cup all-purpose flour, 1 1/2 tsp baking powder, 1/2 tsp baking soda, 2 tsp kosher salt (Diamond Crystal; use 1 tsp if Morton), and 1/3 cup coarse ground cornmeal. Whisk to break up any lumps.

   Time: PT3M

4. Cream Butter, Sugar, and Lemon Zest

   In a large bowl, combine 10 tbsp unsalted butter (room temp), 3/4 cup granulated sugar, and 2 tsp lemon zest. Using a hand mixer, beat on medium-high for about 5 minutes, scraping down the bowl as needed, until the mixture is very pale and fluffy.

   Time: PT7M

5. Add Eggs

   Add 2 large eggs, one at a time, beating well and scraping down the bowl after each addition until fully incorporated.

   Time: PT3M

6. Alternate Dry and Wet Ingredients

   Add about 1/3 of the dry ingredients to the butter mixture and mix on low just until mostly combined. Add half the buttermilk (3/4 cup, room temp) and 2 tsp vanilla extract, mixing gently. Repeat with half the remaining dry, then the rest of the buttermilk, then the last of the dry, mixing just until combined each time. Finish mixing by hand with a spatula to avoid overmixing.

   Time: PT6M

7. Fold in Blueberries

   Add 1.5 lbs blueberries (fresh or frozen) to the batter. Gently fold in with a spatula, being careful not to burst the berries. If using frozen, expect the batter to stiffen and possibly turn purple.

   Time: PT3M

8. Assemble in Pan

   Spoon the thick batter into the prepared pan in dollops to avoid air pockets. Smooth the top with an offset spatula. Evenly sprinkle the streusel topping over the batter.

   Time: PT4M

9. Bake

   Bake in a preheated oven at 350°F (175°C) for 1 hour 30 minutes to 1 hour 40 minutes if using fresh berries, or 1 hour 45 minutes to 1 hour 55 minutes if using frozen. The cake is done when a tester inserted in the center comes out clean and the top is golden and crisp.

   Time: PT1H40M

   Temperature: 350°F

10. Cool and Unmold

    Let the cake cool in the pan for at least 2-3 hours (or overnight) to allow it to set fully. Run a knife around the edge, then remove the springform ring. Serve at room temperature.

    Time: PT12M

11. Cleanup

    Wash mixing bowls, beaters, spatula, offset spatula, whisk, measuring cups and spoons, zester, knife, and springform pan. Wipe down counters and oven area.

    Time: PT10M

Nutrition Facts

Calories

340

Protein

5g

Carbohydrates

54g

Fat

12g

Fiber

3g

Ingredient Substitutions

• Instead of All-purpose flour: Gluten-free all-purpose flour
• Instead of Light brown sugar: Dark brown sugar
• Instead of Unsalted butter: Plant-based butter
• Instead of Kosher salt: Sea salt (reduce amount)
• Instead of Ground cinnamon: Pumpkin pie spice
• Instead of Corn flakes: Rice Krispies, Oat flakes
• Instead of Granulated sugar: Coconut sugar
• Instead of Buttermilk: Milk + 2 tsp lemon juice or vinegar
• Instead of Eggs: Flax eggs
• Instead of Coarse ground cornmeal: Fine cornmeal (texture will differ)
• Instead of Blueberries: Mixed berries
• Instead of Lemon zest: Orange zest
• Instead of Vanilla extract: Vanilla bean paste
• Instead of Parchment paper: Butter and flour for dusting

Equipment Needed

• 10-inch springform pan
• Hand mixer with beaters
• 2 mixing bowls (large and medium)
• Small bowl (optional)
• Flexible spatula
• Offset spatula (optional)
• Pastry brush (optional)
• Measuring cups and spoons
• Whisk
• Zester or microplane
• Knife

Critical Steps — Do Not Skip

• Make the Streusel Topping correctly so it's clumpy and not dry.
• Cream butter and sugar thoroughly for a light cake.
• Measure and use the correct amount of salt for flavor.
• Do not overmix after adding flour to keep cake tender.
• Bake fully; underbaking will result a gummy center.
• Cool completely before unmolding to prevent collapse.

Chef Tips from the Video

• Use wild frozen blueberries for extra flavor.
• Let cake cool overnight for best texture.
• If using Morton kosher salt, reduce to 1 tsp.
• Don't rush the creaming step; it's key for a light crumb.
• If you don't have buttermilk, add 2 tsp lemon juice or vinegar to milk and let sit 5 minutes.

Troubleshooting

Storage

Refrigerator: Store covered for up to 4 days. Bring to room temperature before serving.

Freezer: Wrap tightly and freeze for up to 2 months. Thaw overnight in refrigerator.

Room temperature: Keeps well covered for 1-2 days at cool room temperature.

Make-Ahead Tips

• Cake improves in flavor and texture if made a day ahead.
• Streusel can be made and refrigerated up to 2 days in advance.
• Cake can be frozen whole or in slices.