Costco shoppers can’t get enough of the Lemon-Blueberry Loaf Cake from the bakery, and we’re on board too! So much so, we’ve crafted our own version just for you. Our recipe boasts a tender lemon batter bursting with fresh blueberries, crowned with a crunchy butter streusel topping and tangy lemon glaze that mirrors Costco’s irresistible treat. Now, whether you’re a Costco member or not, you can savor this delightful cake right in your own kitchen.
Some online reviewers mentioned inconsistencies in blueberry distribution and lemon flavor in the original cake. But with our recipe, you’ll nail it every time. You’ll enjoy a perfect balance of blueberries and lemony goodness in both the batter and the glaze.
Tip: Bake this version in a 9″x5″ loaf pan for just the right fit, no need for specialty cookware.
Costco Lemon-Blueberry Pound Cake
Ingredients
**Butter Streusel:**
- 1/4 cup all-purpose flour
- 2 tablespoons granulated sugar
- 2 tablespoons packed light brown sugar
- Large pinch of kosher salt
- 2 tablespoons unsalted butter melted and slightly cooled
**Cake:**
- 1/2 cup safflower or canola oil plus extra for the pan
- 1 3/4 cups all-purpose flour
- 1 cup granulated sugar
- 2 teaspoons baking powder
- 3/4 teaspoon kosher salt
- 3 large eggs
- 1 cup plain Greek yogurt
- 1 tablespoon finely grated lemon zest from about 1 lemon
- 2 teaspoons pure vanilla extract
- 2 cups fresh blueberries divided
**Lemon Icing:**
- 1/2 cup confectioners’ sugar
- 2 teaspoons or more fresh lemon juice
- 1/2 teaspoon light corn syrup
Instructions
**Butter Streusel:**
- Preheat oven to 350°F. In a small bowl, whisk together flour, granulated sugar, brown sugar, and salt. Pour melted butter over dry ingredients and stir until combined. Set aside.
**Cake:**
- Brush a 9″x5″ loaf pan with oil and line it with parchment paper, leaving a 2″ overhang on two opposite long sides. Brush parchment with oil.
- In a medium bowl, whisk together flour, granulated sugar, baking powder, and salt.
- In a large bowl, whisk together eggs, yogurt, lemon zest, vanilla, and oil until well combined. Add dry ingredients to the egg mixture and mix until just combined. Fold in 1 1/2 cups blueberries.
- Pour batter into the prepared pan and smooth the top with a spatula. Scatter remaining 1/2 cup blueberries over the batter and gently press them in. Crumble butter streusel over the top.
- Bake for 1 hour and 20 minutes to 1 hour and 30 minutes, tenting with foil during the last 30 minutes if the top is browning too quickly. A tester inserted into the center should come out clean.
- Let the cake cool in the pan for 10 minutes, then transfer it to a wire rack using the parchment overhang. Remove parchment and let cool completely.
**Lemon Icing:**
- In a medium bowl, whisk together confectioners’ sugar, lemon juice, and corn syrup until smooth and thick yet pourable.
- Drizzle glaze over the cooled cake and let it set for about 30 minutes before serving. Enjoy!